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Kharaeva, Z. F., M. Sh Mustafaev, L. Z. Blieva, E. B. Barokova, S. M. Mustafaeva e S. A. Dyshekova. "Evaluation of sensitivity to bacteriophages of strains isolated from children with congenital malformations of the maxillofacial region". REPORTS ADYGE (CIRCASSIAN) INTERNATIONAL ACADEMY OF SCIENCES 20, n. 1 (2020): 40–45. http://dx.doi.org/10.47928/1726-9946-2020-20-1-40-45.
Testo completoAbstract (sommario):
Bacteriophage are used in clinical practice along with antibiotics. It is known that in many cases phage drugs are superior to other antibacterial drugs in their activity against antibiotic-resistant pathogens. Bacteriophages do not cause toxic or allergic side effects and have no contraindications.The use of bacteriophage preparations stimulates the activation of adaptive and innate immune factors, so phage therapy is particularly effective in the treatment of chronic inflammatory diseases against the background of immunosuppressive States. Bacteriophages do not interfere with the implementation of the therapeutic effect of other drugs (antibiotics, probiotics, synbiotics) and are not sensitive to their effects. The paper evaluates the sensitivity of different types of staphylococci and streptococci to specific bacteriophages, as well as to sextaphage - polyvalent piobacteriophage. In the course of research, it was found that bacterial cultures of Staphylococcus aureus showed a fairly high sensitivity to sextaphage, to which 83,3% (10 strains) of the total number of studied strains of this species were susceptible. Sensitivity to bacteriophages in Staphylococcus epidermidis strains was low. Bacterial strains of Streptococcus pyogenes showed greater susceptibility to streptococcal phage than to sextaphage. 87,5% of the strains were susceptible to streptococcal bacteriophage. Bacterial cultures of Streptococcus salivarius showed moderate susceptibility to bacteriophages.
2
Horiuk, Yu V. "Lytic Activity of Staphylococcal Bacteriophage on Different Biotypes of Staphylococcus aureus". Scientific Messenger of LNU of Veterinary Medicine and Biotechnologies 21, n. 94 (30 luglio 2019): 115–20. http://dx.doi.org/10.32718/nvlvet9421.
Testo completoAbstract (sommario):
Bacteriophage is a virus that infects a bacterium by injecting a phage genome into a bacterial cytoplasm and uses a host cell as a propagation mechanism. The studied models of phages show a narrow range of hosts. Previous studies on the investigation of lytic activity of staphylococcal bacteriophages were focused on determining the sensitivity of S. aureus isolated from patients from different clinical material and clinically healthy people. However, there is no information as to how refractory are the already described agents against S. aureus ecovars, isolated from animals. The purpose of the work is to study the lytic activity of the agent “Staphylococcal Bacteriophage” in relation to different biotypes of Staphylococcus aureus. Microbiological treatment of samples for isolation of S. aureus was performed using BD Baird-Parker Agar according to standard techniques. To confirm the presence of S. aureus, tests were used for catalase, coagulase, oxidase, for D-mannitol fermentation, DNase production and acetoin. In cultures belonging to S. aureus, the biotype was determined using the scheme: determining the colour of pigment, the presence of beta hemolysis, the activity of coagulase in the bovine plasma, the formation of colonies in a medium with crystal violet. Determination of the range of action of bacteriophages in relation to clinical isolates of microorganisms was carried out by droplet method. The results of determining the lytic activity of staphylococcal bacteriophage in relation to S. aureus isolates of various biological origin showed that the lytic activity of staphylococcal bacteriophage is most active against S. aureus var. hominis. From the studied cultures S. aureus var. hominis full lysis in the course of dripping were found only in 4.8%, and in 42.8% of cultures showed a semiconfluent lysis. 14.3% of cultures S. aureus var. hominis were subjected to weak lytic activity of the bacteriophage. Also, there were detected 4,8% of cultures of this biotype, which were resistant to staphylococcal bacteriophage. In the study of lytic activity of staphylococcal bacteriophage up to 35 cultures S. aureus var. bovis, the manifestation of the lytic action of only one culture is established. Moreover, the level of lysis was estimated at “+/–”, that is, they showed less than 20 phage colonies. At the same time, the studied by us staphylococcal bacteriophage did not show the lytic action on S. aureus var. avium and S. aureus var. canis. Therefore, conducted studies have shown that the lytic activity of the agent “Staphylococcal Bacteriophage” is directed mainly to S. aureus var. hominis, and practically does not work on other biotypes. In consideration of the apparent lack of activity of phage agents in relation to the studied biotypes, attention should be focused on the specificity of phages, not only within the species of bacteria, but also within their biotypes.
3
Vorobey, E. S., O. S. Voronkova e A. I. Vinnikov. "Correction of vaginal dysbiosis in mice caused by a film-forming strain Staphylococcus aureus, using bacteriophages and probiotics". Regulatory Mechanisms in Biosystems 8, n. 2 (29 aprile 2017): 252–58. http://dx.doi.org/10.15421/021739.
Testo completoAbstract (sommario):
The complex use of bacteriophages and probiotics is a promising trend in improving prevention and treatment of gynecological lesions. Our study of their influence on the microflora was performed on the model of vaginal dysbiosis of white laboratory mice induced by introduction of a filmforming strain of Staphylococcus aureus. For correction of dysbiosis, staphylococcal bacteriophage liquid, piobacteriophage polyvalent, intesti-bacteriophage liquid and probiotic "Vahilak" were used. For the identification of the microflora of the reproductive tract, samples of biological material from the vagina were obtained by sterile cotton swab and plated on nutrient media to determine the nature and extent of growth of the cultures. The maximal effect was found to occur with the correctional complex "bacteriophage staphylococcal liquid – vahilak" that led to decrease of total microbial number to 4.77 × 104 CFU/ml and to the restoration of the ratio of aerobic to anaerobic bacteria 1 : 52 when indicators of the norm were 4,69 × 104 CFU/ml and 1 : 52. In this case, 24 hours after the last injection of the preparations the amount of microaerophilic and anaerobic lactobacilli had increased by 20.8 and 2.1 times respectively. The frequency of isolation of microaerophilic lactobacilli increased to 100%, and anaerobic – up to 70%. Also the number of staphylococci, streptococci, enterococci, bacilli and enterobacteria decreased by 30.1, 1.1, 1.5, 2.2 and 11.8 times respectively. Also, there was a decrease in the detection rate of enterococci, micrococci and enterobacteria by 10% and bacilli by 20% compared to the control dysbiosis. The number of anaerobic bacteria also underwent significant changes. Thus, the number of fusobacteria decreased by 33.2 times, peptococci – 2.3, peptostreptococci – 6.6 and Bacteroides – 7.9 times, which is almost consistent with indicators of the norm. In addition, the frequency of detection of peptostreptococci decreased by 10%. Therefore, it can be concluded that medical bacteriophages are active against lesions caused by able to film-forming staphylococci, in vivo, so they are appropriate to use in medical practice both independently and in combination with other agents.
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Martykanova, Dilyara, Ilya Zemlenuhin, Ollga Reshetnik, Dilyara Kamaldinova e Nailya Davletova. "Sensitivity of staphylococcus microflora of wrestlers’ skin to bacteriophages". SCIENCE AND SPORT: current trends 7, n. 3 (settembre 2019): 136–41. http://dx.doi.org/10.36028/2308-8826-2019-7-3-136-141.
Testo completoAbstract (sommario):
The purpose of this study was to identify the characteristics of bacteriocenosis of wrestlers’ skin and to determine the sensitivity of staphylococcal microflora to bacteriophages. Methods and organization of the research. The experiment involved 15 athletes aged 17-21 years engaged in national wrestling and belt wrestling. Qualifications ranged from 1st adult rank to the master of sports. We used the method of microbiological seeding on yolk-salt agar (JSA) to analyze the washes from the intact skin of the medial part of forearms of wrestlers before and immediately after training. We identified the grown colonies of microorganisms using MALDI Microflex Biotyper mass-spectrometer (Bruker, Germany). In addition to the total microbial abundance, the frequency of occurrence of hemolytic forms of bacteria on wrestlers’ skin was determined before and after training. We determined the sensitivity of Staphylococcus aureus bacteria to staphylococcal bacteriophage and polyvalent pyobacteriophage by the diameter of the bacteria lysis zone. Results and discussion. The research revealed the following facts. 1) S. aureus appears more often than other staphylococci on the skin of the medial part of wrestlers’ forearms both before and after training. 2) We detected high frequency of occurrence of hemolytic forms of Staphylococcus bacteria, which indicates the dysbiosis of wrestlers’ skin. 3) It is more efficient to use a staphylococcal bacteriophage than polyvalent pyobacteriophage for the prevention and treatment of infectious diseases of wrestlers’ skin caused by S. aureus. Conclusion. Athletes of contact sports demonstrate an increased risk of skin infectious diseases, and they need effective means of protection and prevention.
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Levanova, L. A., Yu V. Zakharova, A. A. Markovskaya e L. Yu Otdushkina. "Bacteriophage sensitivity of opportunistic microbiota in children with gut dysbiosis". Fundamental and Clinical Medicine 7, n. 3 (30 settembre 2022): 40–45. http://dx.doi.org/10.23946/2500-0764-2022-7-3-40-45.
Testo completoAbstract (sommario):
Aim. As the activity of bacteriophages is species- and strain-specific, it is necessary to study bacteriophage sensitivity in distinct geographic regions with various disease patterns. Here, we aimed to study the lytic activity of specific commercially available bacteriophages against Klebsiella spp., Proteus spp., and Staphylococcus aureus isolated from the intestines of children with gut dysbiosis.Materials and Methods. Bacteriophage sensitivity was assessed in 315 opportunistic microorganisms (125 Staphylococcus aureus strains, 120 Klebsiella spp. strains, 70 Proteus spp. strains) isolated from the intestinal microbiota of 300 children < 4 years of age with gut dysbiosis. Bacteriophage preparations were produced by Microgen (Russian Federation). The lytic activity of bacteriophages was studied by a drip method on a Muller-Hinton medium by calculating the area of bacterial culture lysis.Results. We found low sensitivity of Klebsiella spp. (37.5% sensitive strains) and Proteus spp. (41.4% sensitive strains) to specific bacteriophages, albeit there were considerable differences between distinct Klebsiella species (Klebsiella pneumoniae, 56.7% sensitive strains; Klebsiella oxytoca, 18.3% sensitive strains, p = 0.03) and Proteus species (Proteus vulgaris, 52.0% strains; Proteus mirabilis, 35.6% strains, p = 0.04). Nevertheless, sensitivity to Staphylococcus aureus was considerably higher (78.4%). In addition, lytic activity of bacteriophages reduced along with the increasing severity of gut dysbiosis.Conclusion. Klebsiella spp. and Proteus spp. isolated from children with dysbiosis have low sensitivity to commercially available bacteriophages. Bacteriophage sensitivity positively correlated with gut dysbiosis.
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Horiuk, Y., M. Kukhtyn, V. Horiuk, S. Kernychnyi e L. Tarasenko. "Characteristics of bacteriophages of the Staphylococcus aureus variant bovis". Veterinární Medicína 65, No. 10 (29 ottobre 2020): 421–26. http://dx.doi.org/10.17221/55/2020-vetmed.
Testo completoAbstract (sommario):
Bacteriophages may be an alternative method of treatment for antibiotic-resistant bacteria, including mastitis in cows. Our study describes the initial isolation and bacteriological activity of bacteriophages, circulating on dairy farms, the against S. aureus var. bovis. Samples of cow’s milk secretions with signs of mastitis and sewage water were used as the study material. The isolation and production of pure bacteriophage lines were performed according to the double agar method. The method of studying a single cycle of phage reproduction was used to determine the duration of the latency period. Determination of the spectrum of the lytic activity of bacteriophages against the clinical isolates of the microorganisms was carried out by the drop method. As a result of the research, four phages, specific for S. aureus var. bovis were isolated: Phage SAvB07, Phage SAvB08, Phage SAvB12 and Phage SAvB14. The negative colonies of the isolated phages were 1–2 mm in size, rounded with clear edges, with varying degrees of transparency. The latency period of Phage SAvB14 was 35 min, with the number of active virions increasing by 8 orders. In the study on growth curves of other bacteriophages, taken in the experiment, the latency period was more than 35 min, and their titre increased by only two orders. Phage SAvB07, Phage SAvB08 and Phage SAvB12 were able to lyse the bacterial strains of S. aureus var. bovis in 25–45.6% of the cases (low lytic activity), whereas Phage SAvB14 lysed 94.1% of S. aureus strains were isolated from the cows. Studies have shown that among the bacteriophages we have studied, Phage SAvB14 with a short latency period has the best lytic action on the culture S. aureus var. bovis. The resulting bacteriophage strain can be used to create a bacteriophage-based drug for the treatment of mastitis in cows.
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Rybalkin, M. V., N. V. Khokhlenkova e К. Yе Nikiforova. "The study of the effectiveness of the antibacterial action of the combination of a bacteriophage with a probiotic". News of Pharmacy 103, n. 1 (7 febbraio 2022): 60–65. http://dx.doi.org/10.24959/nphj.22.83.
Testo completoAbstract (sommario):
Intestinal infections occupy one of the leading places in diseases of the gastrointestinal tract in humans and animals. Strains of Staphylococcus spp are one of the causative agents of an intestinal infection. When treating an intestinal infection caused by staphylococcus, antibiotics are most often used, but in recent years there has been the formation of resistance in staphylococcus strains to antibiotics that have been used for many years. One of the promising ways to solve the problem of antimicrobial resistance is the use of drugs based on bacteriophages, which have a specific effect on the disease pathogens, however, they are free of toxic and allergenic side effects on the human body and do not cause resistance. Aim. To study the antibacterial effect of the combination of a staphylococcal bacteriophage and a probiotic based on L. acidophilus lactobacilli to different staphylococcal strains. Materials and methods. The following bacterial strains were used in the study: St. aureus ATCC 25923 and St. epidermidis ATCC 12228. The “Polyphag Staf” staphylococcal bacteriophage (manufactured by NVK MVK, Ukraine) and the “Lactofor” probiotic (manufactured by Ananta Medicare Limited, India) based on L. acidophilus lactobacilli were selected as objects. In the study, the antibiotic “Erythromycin” in tablets of 100 mg (the manufacturer – Borschagovsky HFZ, Ukraine) was used as a reference drug. To detect the antibacterial activity to the experimental strains of St. aureus and St. epidermidis, the methods of Appelman and agar diffusion were used. Results and discussion. It was found that when using the combination of a staphylococcal bacteriophage and a probiotic with L. acidophilus lactobacilli the level of the antibacterial activity to the experimental strains of St. aureus and St. epidermidis was higher than when using only the bacteriophage. This is probably due to the synergism of the interaction of the components of the combination of active substances proposed. It was also found that the antibacterial activity of the combination of drugs and the antibiotic erythromycin proposed was at the same level. Thus, the combination of a bacteriophage that destroys staphylococcal bacteria, has no side effects, and does not cause resistance and a probiotics that improves the microflora of the gastrointestinal tract has a number of advantages over antibioticsin the treatment of intestinal infections caused by staphylococcal strains. Conclusions. The studies conducted indicate the prospects of using the combination of a staphylococcal bacteriophage and a probiotic based on L. acidophilus lactobacilli for the treatment of intestinal infections caused by different staphylococcal strains.
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Kuptsov, NS, MA Kornienko, RB Gorodnichev, DI Danilov, MV Malakhova, TV Parfenova, GI Makarenko, EA Shitikov e EN Ilina. "Efficacy of commercial bacteriophage products against ESKAPE pathogens". CIRCULATING RNA, n. (3)2020 (25 maggio 2020): 18–24. http://dx.doi.org/10.24075/brsmu.2020.029.
Testo completoAbstract (sommario):
The ever-rising prevalence of multidrug-resistant bacteria necessitates the search for a therapeutic alternative to antibiotics. Using therapeutic products based on virulent bacteriophages might provide such an alternative. The aim of our study was to evaluate the efficacy of commercial phage products and natural bacteriophage monoisolates recovered from environmental sources against clinical strains of Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa. We compiled a collection of 147 strains that were subsequently genotypes using the MLST method. The efficacy of bacteriophages was evaluated in spot tests. The highest efficacy was demonstrated by "Staphylococcal bacteriophage" (86%, effective against S. aureus), "Purified polyvalent pyobacteriophage" (87.8%, effective against K. pneumoniae), and a group of phage products against P. aeruginosa, including "Pseudomonas aeruginosa bacteriophage" (87.5%), "Complex pyobacteriophage" (79.5–90%) and "Purified polyvalent pyobacteriophage" (90–92.5%). The efficacy of "Intesti bacteriophage", which targets E. faecium, was 4.2%. The efficacy of commercial phage products against S. aureus and K. pneumoniae was higher than the efficacy of individual phage monoisolates (60% for the S. aureus phage vB_SauP-436-3w and 5.9% for the K. pneumoniae phage vB_Kp_M_ Seu621). Thus, all tested commercial phage products were highly effective against P. aeruginosa, K. pneumoniae and S. aureus. There are no commercial phage products on the market against other ESKAPE pathogens, including Acinetobacter baumannii and Enterobacter cloacae. Besides, there are no effective phage products against E. faecium. This dictates the need for new effective bacteriophages against these species.
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Aleksanina, N. V., e T. I. Tverdokhlebova. "Phage resistance of conditionally pathogenic intestinal microbiota bacteria in children with microbiocenosis disorders". Journal Infectology 13, n. 2 (14 luglio 2021): 102–7. http://dx.doi.org/10.22625/2072-6732-2021-13-2-102-107.
Testo completoAbstract (sommario):
Objective: to study the circulation and prevalence of phage-resistant strains among opportunistic enterobacteria, isolated from children with disorders of intestinal microflora, in relation to domestic preparations of bacteriophages.Materials and methods. A bacteriological study of the fecal microflora of the colon in 970 young children for dysbiosis was carried out. The sensitivity of 720 antibiotic-resistant strains of opportunistic enterobacteriaceae (S. aureus, K. pneumoniae, P. mirabilis and P. vulgaris, P. aeruginosa, E. coli, coagulase-negative staphylococci) isolated from children to domestic mono- and polyvalent drugs was studied (coliprotein, staphylococcal, Pseudomonas aeruginosa, purified Klebsiella pneumonia bacteriophage, “Sextafag”, Intesta bacteriophage). Determination of sensitivity to bacteriophages was carried out by the “sterile spot” method. Antibiotic sensitivity was determined by the disk diffusion method. Statistical processing of the results was carried out using the Microsoft Office Excel 2007 software package.Results. A large percentage of phage-resistant strains with low sensitivity to bacteriophages was revealed among opportunistic bacteria, amounting to 54,2%, with the highest circulation among coagulase-negative staphylococci, Proteus, Klebsiella (more than 50%). A significant spread of intestinal dysbiosis was established in young children (87,5%), characterized by a low content of bifidobacteria and a high level of allocation of opportunistic enterobacteria, including in associations.Conclusion. As a result of the studies, a significant prevalence of phage-resistant strains in children with dysbiosis was revealed, which indicates the need for preliminary determination of their sensitivity to bacteriophages in order to resolve the issue of their possible inclusion in the intestinal microflora correction system.
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Horiuk, Y. V., M. D. Kukhtyn, Y. S. Stravskyy, S. I. Klymnyuk, K. M. Vergeles e V. V. Horiuk. "Influence of staphylococcal Phage SAvB14 on biofilms, formed by Staphylococcus aureus variant bovis". Regulatory Mechanisms in Biosystems 10, n. 3 (22 agosto 2019): 314–18. http://dx.doi.org/10.15421/021948.
Testo completoAbstract (sommario):
The use of bacteriophages for the treatment of chronic inflammatory processes has proved to be relevant, especially during isolation of antibiotic-resistant pathogens formed in biofilms. The article presents the results of research on the influence of Phage SAvB14 on young and mature biofilms formed by Staphylococcus aureus variant bovis. In the experiments we used cultures of S. aureus and a specific Phage SAvB14 isolated from the secretion of the mammary gland of cows suffering from chronic mastitis. In the study of the influence of bacteriophage on formed biofilms we determined the optical density of the dye solution that was washed from the biofilm photometrically on a spectrophotometer PE-5400UV (Ecroskhim, Russia) and the number of staphylococcal cells in the biofilm after the action of the bacteriophage on 24-hour and 72-hour biofilms by a ten-fold dilution on beef-extract agar. It was determined that under the influence of the bacteriophage on young 24-hour biofilms of S. aureus var. bovis, the optical density of the dye solution from biofilm increased within 4 hours up to 10% and the number of microbial cells increased by 1.8 times. After 32 hours of bacteriophage action, the optical density of the dye solution decreased on average by 34% compared to the initial density and the number of S. aureus cells in the biofilm decreased by 30 times. This indicates that microbial cells of young biofilms are not subject to complete lysis during the action of even this specific bacteriophage. Degradation of 77.5% of biofilm under the influence of the bacteriophage was observed on mature 72-hour biofilm within 32 hours at 37 °C. At the same time, viable cells of S. aureus were not isolated from the biofilm. This indicates the high lytic activity of the bacteriophage against mature biofilm bacteria and the possibility of its use in chronic staphylococcal infections caused by S. aureus var. bovis. Thus, the obtained data indicate that when mature 72-hour biofilms are exposed to the researched bacteriophage, their degradation is more intense compared with the young 24-hour biofilms, and the amount of destroyed biofilm was on average 2 times higher. This suggests that the use of specific staphylococcal Phage SAvB14 isolated by us for the destruction of biofilm, formed by S. aureus var. bovis, is promising.
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Kimirilova, O. G., e G. A. Kharchenko. "Results of treatment of primary staphylococcal enterocolitis in infants with the use of antibacterial drugs and their combination with bacteriophages: a prospective study". CHILDREN INFECTIONS 20, n. 3 (6 ottobre 2021): 33–38. http://dx.doi.org/10.22627/2072-8107-2021-20-3-33-38.
Testo completoAbstract (sommario):
In infectious pathology in infants, staphylococcal infection occupies a leading place, is characterized by the rapid development of intoxication, a purulent-destructive process with the possibility of generalization of infection, affecting the course and outcome of the disease.The aim of the study was to study the results of treatment of primary staphylococcal enterocolitis, in infants, with the use of antibacterial drugs and their combination with bacteriophages.Research methods. The frequency of elimination of staphylococcus, the duration of the main symptoms (fever, diarrhea, toxicosis with exicosis) as a result of treatment of primary staphylococcal enterocolitis (confirmed by laboratory) were analyzed in children aged from 1 to 12 months who received inpatient antibacterial drugs (nifuroxazide, azithromycin) or their combination with bacteriophages (staphylococcal, pyobacteriophage). The data accounting period is from January 2017 to December 2020.The results of the study. The results of treatment of staphylococcal enterocolitis were studied in 4 groups: monotherapy with nifuroxazide (n = 39) or azithromycin (n = 40), a combination of nifroxazide+staphylococcal bacteriophage (n = 41) or azithromycin + piobacteriphage (n = 38). The groups were comparable by gender, age, and clinical manifestations of the disease. Elimination of staphylococcus on the 10th—12th day. treatment with monotherapy with antibacterial drugs was achieved in 31—35%, with their combination with bacteriophages — in 51—64% of patients in each combination (df = 3, p < 0.05). Against the background of combined therapy, the symptoms of the disease (diarrhea, vomiting) were stopped 1.2 times faster; the number of patients with lactase deficiency and intestinal dysbiosis decreased by 1.7—2 times, with monotherapy with antibacterial drugs-by 1.3—1.4 times (df = 3, p < 0.05).Conclusion. Treatment of primary staphylococcal enterocolitis in children, including antibacterial drugs and bacteriophages, is more effective than monotherapy with antibacterial drugs.
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Frosini, Sian Marie, Ross Bond, Alex J. McCarthy, Claudia Feudi, Stefan Schwarz, Jodi A. Lindsay e Anette Loeffler. "Genes on the Move: In Vitro Transduction of Antimicrobial Resistance Genes between Human and Canine Staphylococcal Pathogens". Microorganisms 8, n. 12 (18 dicembre 2020): 2031. http://dx.doi.org/10.3390/microorganisms8122031.
Testo completoAbstract (sommario):
Transmission of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus pseudintermedius (MRSP) between people and pets, and their co-carriage, are well-described. Potential exchange of antimicrobial resistance (AMR) genes amongst these staphylococci was investigated in vitro through endogenous bacteriophage-mediated transduction. Bacteriophages were UV-induced from seven donor isolates of canine (MRSP) and human (MRSA) origin, containing tet(M), tet(K), fusB or fusC, and lysates filtered. Twenty-seven tetracycline- and fusidic acid- (FA-) susceptible recipients were used in 122 donor-recipient combinations (22 tetracycline, 100 FA) across 415 assays (115 tetracycline, 300 FA). Bacteriophage lysates were incubated with recipients and presumed transductants quantified on antimicrobial-supplemented agar plates. Tetracycline resistance transduction from MRSP and MRSA to methicillin-susceptible S. pseudintermedius (MSSP) was confirmed by PCR in 15/115 assays. No FA-resistance transfer occurred, confirmed by negative fusB/fusC PCR, but colonies resulting from FA assays had high MICs (≥32 mg/L) and showed mutations in fusA, two at a novel position (F88L), nine at H457[Y/N/L]. Horizontal gene transfer of tetracycline-resistance confirms that resistance genes can be shared between coagulase-positive staphylococci from different hosts. Cross-species AMR transmission highlights the importance of good antimicrobial stewardship across humans and veterinary species to support One Health.
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Mannala, GK, M. Rupp, N. Walter, M. Brunotte, F. Alagboso, D. Docheva, C. Brochhausen e V. Alt. "Microbiological and ultrastructural evaluation of bacteriophage 191219 against planktonic, intracellular and biofilm infection with Staphylococcus aureus". European Cells and Materials 43 (24 febbraio 2022): 66–78. http://dx.doi.org/10.22203/ecm.v043a07.
Testo completoAbstract (sommario):
Infections of orthopaedic implants, such as fracture fixation devices and total-joint prostheses, are devastating complications. Staphylococcus aureus (S. aureus) is a predominant pathogen causing orthopaedic-implant biofilm infections that can also internalise and persist in osteoblasts, thus resisting antibiotic therapy. Bacteriophages are a promising alternative treatment approach. However, data on the activity of bacteriophages against S. aureus, especially during intracellular growth, and against in vivo biofilm formation on metals are scarce. Therefore, the present study evaluated the in vitro efficacy of S. aureus bacteriophage 191219, alone as well as in combination with gentamicin and rifampicin, to eradicate S. aureus strains in their planktonic stage, during biofilm formation and after internalisation into osteoblasts. Further, the invertebrate model organism Galleria mellonella was used to assess the activity of the bacteriophage against S. aureus biofilm on metal implants with and without antibiotics. Results demonstrated the in vitro efficacy of bacteriophage 191219 against planktonic S. aureus. The phage was also effective against in vitro S. aureus biofilm formation in a dose-dependent manner and against S. aureus internalised in an osteoblastic cell line. Transmission electron microscopy (TEM) analysis showed bacteriophages on S. aureus inside the osteoblasts, with the destruction of the intracellular bacteria and formation of new bacteriophages. For the Galleria mellonella infection model, single administration of phage 191219 failed to show an improvement in survival rate but appeared to show a not statistically significant enhanced effect with gentamicin or rifampicin. In summary, bacteriophages could be a potential adjuvant treatment strategy for patients with implant-associated biofilm infections.
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Brown, Matthew, Alex Hall, Henriett Zahn, Marcia Eisenberg e Stephen Erickson. "Bacteriophage-Based Detection of Staphylococcus aureus in Human Serum". Viruses 14, n. 8 (10 agosto 2022): 1748. http://dx.doi.org/10.3390/v14081748.
Testo completoAbstract (sommario):
Bacteriophages have been investigated for clinical utility, both as diagnostic tools and as therapeutic interventions. In order to be applied successfully, a detailed understanding of the influence of the human matrix on the interaction between bacteriophage and the host bacterium is required. In this study, a cocktail of luciferase bacteriophage reporters was assessed for functionality in a matrix containing human serum and spiked with Staphylococcus aureus. The inhibition of signal and loss of sensitivity was evident with minimal amounts of serum. This phenotype was independent of bacterial growth and bacteriophage viability. Serum-mediated loss of signal was common, albeit not universal, among S. aureus strains. Immunoglobulin G was identified as an inhibitory component and partial inhibition was observed with both the f(ab’)2 and Fc region. A modified bacteriophage cocktail containing recombinant protein A was developed, which substantially improved signal without the need for additional sample purification. This study highlights the importance of assessing bacteriophage activity in relevant host matrices. Furthermore, it identifies an effective solution, recombinant protein A, for promoting bacteriophage-based detection of S. aureus in matrices containing human serum.
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Rai, Akanksha, e Krishna Khairnar. "Initial Survey of Staphylococcus Bacteriophages and Simple Modifications in the Enrichment Method for Enhancing Plaques". Research Journal of Biotechnology 17, n. 7 (25 giugno 2022): 130–33. http://dx.doi.org/10.25303/1707rjbt1300133.
Testo completoAbstract (sommario):
Isolation of bacteriophages against Staphylococcus aureus is difficult when compared to the bacteriophages of other genera. We did a preliminary survey for the presence of bacteriophages of S. aureus and Escherichia coli in the environmental water samples. We did not get bacteriophages against S. aureus, but bacteriophages against E. coli were ample. Subsequently, a river-water sample was taken and through the enrichment method with some modifications, we got a bacteriophage against a methicillin-resistant S. aureus. Here, we are reporting simple changes in the enrichment method to enhance plaques that have an extremely tiny and turbid morphology. This can be useful for researchers facing difficulty in finding lytic bacteriophages from water samples.
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Grygorcewicz, Bartłomiej, Rafał Rakoczy, Marta Roszak, Maciej Konopacki, Marian Kordas, Agnieszka Piegat, Natalia Serwin, Elżbieta Cecerska-Heryć, Miroslawa El Fray e Barbara Dołęgowska. "Rotating Magnetic Field-Assisted Reactor Enhances Mechanisms of Phage Adsorption on Bacterial Cell Surface". Current Issues in Molecular Biology 44, n. 3 (17 marzo 2022): 1316–25. http://dx.doi.org/10.3390/cimb44030088.
Testo completoAbstract (sommario):
Growing interest in bacteriophage research and use, especially as an alternative treatment option for multidrug-resistant bacterial infection, requires rapid development of production methods and strengthening of bacteriophage activities. Bacteriophage adsorption to host cells initiates the process of infection. The rotating magnetic field (RMF) is a promising biotechnological method for process intensification, especially for the intensification of micromixing and mass transfer. This study evaluates the use of RMF to enhance the infection process by influencing bacteriophage adsorption rate. The RMF exposition decreased the t50 and t75 of bacteriophages T4 on Escherichia coli cells and vb_SauM_A phages on Staphylococcus aureus cells. The T4 phage adsorption rate increased from 3.13 × 10−9 mL × min−1 to 1.64 × 10−8 mL × min−1. The adsorption rate of vb_SauM_A phages exposed to RMF increased from 4.94 × 10−9 mL × min−1 to 7.34 × 10−9 mL × min−1. Additionally, the phage T4 zeta potential changed under RMF from −11.1 ± 0.49 mV to −7.66 ± 0.29 for unexposed and RMF-exposed bacteriophages, respectively.
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Zhou, Wenyuan, Hua Wen, Yajie Li, Yajun Gao, Xiangfeng Zheng, Lei Yuan, Guoqiang Zhu e Zhenquan Yang. "Whole-Genome Analysis Reveals That Bacteriophages Promote Environmental Adaptation of Staphylococcus aureus via Gene Exchange, Acquisition, and Loss". Viruses 14, n. 6 (31 maggio 2022): 1199. http://dx.doi.org/10.3390/v14061199.
Testo completoAbstract (sommario):
The study of bacteriophages is experiencing a resurgence owing to their antibacterial efficacy, lack of side effects, and low production cost. Nonetheless, the interactions between Staphylococcus aureus bacteriophages and their hosts remain unexplored. In this study, whole-genome sequences of 188 S. aureus bacteriophages—20 Podoviridae, 56 Herelleviridae, and 112 Siphoviridae—were obtained from the National Center for Biotechnology Information (NCBI, USA) genome database. A phylogenetic tree was constructed to estimate their genetic relatedness using single-nucleotide polymorphism analysis. Comparative analysis was performed to investigate the structural diversity and ortholog groups in the subdividing clusters. Mosaic structures and gene content were compared in relation to phylogeny. Phylogenetic analysis revealed that the bacteriophages could be distinguished into three lineages (I–III), including nine subdividing clusters and seven singletons. The subdividing clusters shared similar mosaic structures and core ortholog clusters, including the genes involved in bacteriophage morphogenesis and DNA packaging. Notably, several functional modules of bacteriophages 187 and 2368A shared more than 95% nucleotide sequence identity with prophages in the S. aureus strain RJ1267 and the Staphylococcus pseudintermedius strain SP_11306_4, whereas other modules exhibited little nucleotide sequence similarity. Moreover, the cluster phages shared similar types of holins, lysins, and DNA packaging genes and harbored diverse genes associated with DNA replication and virulence. The data suggested that the genetic diversity of S. aureus bacteriophages was likely due to gene replacement, acquisition, and loss among staphylococcal phages, which may have crossed species barriers. Moreover, frequent module exchanges likely occurred exclusively among the subdividing cluster phages. We hypothesize that during evolution, the S. aureus phages enhanced their DNA replication in host cells and the adaptive environment of their host.
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Plota, Maria, Eleni Sazakli, Nikolaos Giormezis, Foteini Gkartziou, Fevronia Kolonitsiou, Michalis Leotsinidis, Sophia G. Antimisiaris e Iris Spiliopoulou. "In Vitro Anti-Biofilm Activity of Bacteriophage K (ATCC 19685-B1) and Daptomycin against Staphylococci". Microorganisms 9, n. 9 (31 agosto 2021): 1853. http://dx.doi.org/10.3390/microorganisms9091853.
Testo completoAbstract (sommario):
The purpose of the present study was to investigate anti-staphylococcal activity of daptomycin and bacteriophage K, alone or in combination, against biofilm-producers and non-producers S. aureus and S. epidermidis strains, under biofilm forming and cells’ proliferation conditions. Daptomycin and bacteriophage K (ATCC 19685B1), in different concentrations, were tested against 10 Staphylococcus aureus and 10 S. epidermidis, characterized by phenotypes and genotypes. The quantitative microtiter plate (crystal violet, CV), methylthiazoltetrazolium (MTT), and growth curve (GC) assays were performed. No statistically significant difference was found between species, whereas daptomycin alone performed better using medium and high concentrations of the drug and bacteriophage K was more active against strains with higher susceptibility, by CV and MTT assays. Best results were achieved using both agents combined in high concentrations. Bacteriophage K was effective within 3.8 and 2.4 h, depending on the concentration used, by the GC assay. Combination of daptomycin with bacteriophage K was more effective against staphylococci, depending on the concentrations used and strains’ susceptibility. Further studies are needed to evaluate if this approach might be a choice for prevention or therapy of biofilm-associated infections.
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Stipniece, Liga, Dace Rezevska, Juta Kroica e Karlis Racenis. "Effect of the Biopolymer Carrier on Staphylococcus aureus Bacteriophage Lytic Activity". Biomolecules 12, n. 12 (14 dicembre 2022): 1875. http://dx.doi.org/10.3390/biom12121875.
Testo completoAbstract (sommario):
The use of implant materials is always associated with the risk of infection. Moreover, the effectiveness of antibiotics is reduced due to antibiotic-resistant pathogens. Thus, selecting the appropriate alternative antimicrobials for local delivery systems is correlated with successful infection management. We evaluated immobilization of the S. aureus specific bacteriophages in clinically recognized biopolymers, i.e., chitosan and alginate, to control the release profile of the antimicrobials. The high-titre S. aureus specific bacteriophages were prepared from commercial bacteriophage cocktails. The polymer mixtures with the propagated bacteriophages were then prepared. The stability of the S. aureus bacteriophages in the biopolymer solutions was assessed. In the case of chitosan, no plaques indicating the presence of the lytic bacteriophages were observed. The titre reduction of the S. aureus bacteriophages in the Na-alginate was below 1 log unit. Furthermore, the bacteriophages retained their lytic activity in the alginate after crosslinking with Ca2+ ions. The release of the lytic S. aureus bacteriophages from the Ca-alginate matrices in the TRIS-HCl buffer solution (pH 7.4 ± 0.2) was determined. After 72 h—0.292 ± 0.021% of bacteriophages from the Ca-alginate matrices were released. Thus, sustained release of the lytic S. aureus bacteriophages can be ensured.
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Crane, Adele, Joy Abaidoo, Gabriella Beltran, Danielle Fry, Colleen Furey, Noe Green, Ravneet Johal et al. "The Complete Genome Sequence of the Staphylococcus Bacteriophage Metroid". G3 Genes|Genomes|Genetics 10, n. 9 (1 settembre 2020): 2975–79. http://dx.doi.org/10.1534/g3.120.401365.
Testo completoAbstract (sommario):
Abstract Phages infecting bacteria of the genus Staphylococcus play an important role in their host’s ecology and evolution. On one hand, horizontal gene transfer from phage can encourage the rapid adaptation of pathogenic Staphylococcus enabling them to escape host immunity or access novel environments. On the other hand, lytic phages are promising agents for the treatment of bacterial infections, especially those resistant to antibiotics. As part of an ongoing effort to gain novel insights into bacteriophage diversity, we characterized the complete genome of the Staphylococcus bacteriophage Metroid, a cluster C phage with a genome size of 151kb, encompassing 254 predicted protein-coding genes as well as 4 tRNAs. A comparative genomic analysis highlights strong similarities – including a conservation of the lysis cassette – with other Staphylococcus cluster C bacteriophages, several of which were previously characterized for therapeutic applications.
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Titze, Isabel, Tatiana Lehnherr, Hansjörg Lehnherr e Volker Krömker. "Efficacy of Bacteriophages Against Staphylococcus aureus Isolates from Bovine Mastitis". Pharmaceuticals 13, n. 3 (26 febbraio 2020): 35. http://dx.doi.org/10.3390/ph13030035.
Testo completoAbstract (sommario):
The lytic efficacy of bacteriophages against Staphylococcus aureus isolates from bovine milk was investigated in vitro, regarding possible applications in the therapy of udder inflammation caused by bacterial infections (mastitis). The host range of sequenced, lytic bacteriophages was determined against a collection of 92 Staphylococcus (S.) aureus isolates. The isolates originated from quarter foremilk samples of clinical and subclinical mastitis cases. A spot test and a subsequent plaque assay were used to determine the phage host range. According to their host range, propagation and storage properties, three phages, STA1.ST29, EB1.ST11, and EB1.ST27, were selected for preparing a bacteriophage mixture (1:1:1), which was examined for its lytic activity against S. aureus in pasteurized and raw milk. It was found that almost two thirds of the isolates could be lysed by at least one of the tested phages. The bacteriophage mixture was able to reduce the S. aureus germ density in pasteurized milk and its reduction ability was maintained in raw milk, with only a moderate decrease compared to the results in pasteurized milk. The significant reduction ability of the phage mixture in raw milk promotes further in vivo investigation.
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Samokhin, A. G., Ju N. Kozlova, D. V. Korneev, O. S. Taranov, E. A. Fedorov, V. V. Pavlov, V. V. Morozova e N. V. Tikunova. "Experimental study of the antibacterial activity of the lytic Staphylococcus aureus bacteriophage ph20 and lytic Pseudomonas aeruginosa bacteriophage ph57 during modelling of its impregnation into poly(methylmetacrylate) orthopedic implants (bone cement)". Annals of the Russian academy of medical sciences 73, n. 1 (1 febbraio 2018): 59–68. http://dx.doi.org/10.15690/vramn905.
Testo completoAbstract (sommario):
Background: The problem of bacterial colonization of implants used in medical practice continues to be relevant regardless of the material of the implant. Particular attention deserves polymeric implants, which are prepared ex tempore from polymethyl methacrylate, for example - duting orthopedic surgical interventions (so-called "bone cement"). The protection of such implants by antibiotic impregnation is subjected to multiple criticisms, therefore, as an alternative to antibiotics, lytic bacteriophages with a number of unique advantages can be used - however, no experimental studies have been published on the possibility of impregnating bacteriophages into polymethyl methacrylate and their antibacterial activity assessment under such conditions.Aims: to evaluate the possibility of physical placement of bacteriophages in polymethylmethacrylate and to characterize the lytic antibacterial effect of two different strains of bacteriophages when impregnated into polymer carrier ex tempore during the polymerization process in in vitro model.Materials and methods: First stage - Atomic force microscopy (AFM) of polymethyl methacrylate samples for medical purposes was used to determine the presence and size of caverns in polymethyl methacrylate after completion of its polymerization at various reaction temperatures (+6…+25°C and +18…+50°C).The second stage was performed in vitro and included an impregnation of two different bacteriophage strains (phage ph20 active against S. aureus and ph57 active against Ps. aeruginosa) into polymethyl methacrylate during the polymerization process, followed by determination of their antibacterial activity.Results: ACM showed the possibility of bacteriophages placement in the cavities of polymethyl methacrylate - the median of the section and the depth of cavities on the outer surface of the polymer sample polymerized at +18…+50°C were 100.0 and 40.0 nm, respectively, and on the surface of the transverse cleavage of the sample - 120.0 and 100.0 nm, respectively, which statistically did not differ from the geometric dimensions of the caverns of the sample polymerized at a temperature of +6…+25°C.The study of antibacterial activity showed that the ph20 bacteriophage impregnated in polymethyl methacrylate at +6…+25°C lost its effective titer within the first six days after the start of the experiment, while the phage ph57 retained an effective titer for at least 13 days.Conclusion: the study confirmed the possibility of bacteriophages impregnation into medical grade polymethyl methacrylate, maintaining the effective titer of the bacteriophage during phage emission into the external environment, which opens the way for the possible application of this method of bacteriophage delivery in clinical practice. It is also assumed that certain bacteriophages are susceptible to aggressive influences from the chemical components of "bone cement" and / or polymerization reaction products, which requires strict selection of bacteriophage strains that could be suitable for this method of delivery.
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Burova, L., O. Korniychuk, S. Pavliy e Y. Mazepa. "Comparative characteristics antimicrobial activity of different classes of antibiotics and antimicrobial isolates on Staphylococcus aureus". Reports of Vinnytsia National Medical University 24, n. 1 (18 maggio 2020): 12–16. http://dx.doi.org/10.31393/reports-vnmedical-2020-24(1)-02.
Testo completoAbstract (sommario):
Annotation. S. aureus is a leading cause of nosocomial infections in health care facilities. The aim of the study was to determine the effectiveness of the use of staphylococcal bacteriophage, phytopreparation “Chlorophyllipt”, of the drug “Protargol”, compared with antimicrobial chemotherapeutic drugs (ACD) against isolates of Staphylococcus aureus in vitro. Used clinical strains of S. aureus, isolated from 20 patients, aged 19 to 25 years. The susceptibility of microorganisms to ACD was determined on the MPA medium by disk-diffusion method. Staphylococcal bacteriophage sensitivity scores were evaluated by drainage lysis of bacterial indicator culture and negative phage colonies. Anti-staphylococcal activity of phytopreparation and protargol solution was determined by diffusion in agar with the isolates tested. Statistical data processing was performed using Microsoft Excel 2013. In determining the susceptibility of S. aureus isolates to ACD, 30% of penicillin-sensitive strains were detected. Amoxicillin sensitivity was 25% of strains. The rate of detected sensitivity of microorganisms to amoxiclav was 45% of strains. Sensitivity to cephalosporins I-II generation amounted to 75% cephalexin, cefazolin, cefuroxime — 90%. For cephalosporins of the third generation — from 70% to 95%; to macrolides: to clarithromycin — 80%, to erythromycin, azithromycin — 50%, 55% respectively. High sensitivity was reported for lincomycin — 80%. The studied strains showed absolute sensitivity to amikacin (100%). 95% strains were sensitive to gentamicin. Not exceed 60–65% sensitivity to tetracyclines and fluoroquinolones. All bacterial isolates were sensitive to bacteriophage. High antimicrobial activity in up to chlorophyllipt was detected in up to 8 test strains. 19 strains have had low-sensitivity to protargol. The results obtained indicate the feasibility of bacteriophages in the medical practice and the continuation of microbiological studies with the study of antimicrobial activity of herbal drugs.
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Capparelli, Rosanna, Marianna Parlato, Giorgia Borriello, Paola Salvatore e Domenico Iannelli. "Experimental Phage Therapy against Staphylococcus aureus in Mice". Antimicrobial Agents and Chemotherapy 51, n. 8 (21 maggio 2007): 2765–73. http://dx.doi.org/10.1128/aac.01513-06.
Testo completoAbstract (sommario):
ABSTRACT The present study describes a bacteriophage (MSa) active against Staphylococcus aureus, including methicillin-resistant staphylococcal strains. When inoculated into mice simultaneously with S. aureus A170 (108 CFU/mouse), phage (109 PFU) rescued 97% of the mice; when applied to nonlethal (5 × 106 CFU/mouse) 10-day infections, the phage also fully cleared the bacteria. The phage MSa, delivered inside macrophages by S. aureus, kills the intracellular staphylococci in vivo and in vitro. The phage can also prevent abscess formation and reduce the bacterial load and weight of abscesses. These results suggest a potential use of the phage for the control of both local and systemic human S. aureus infections.
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Abbas, Rao Zahid, Abdullah F. Alsayeqh e Amjad Islam Aqib. "Role of Bacteriophages for Optimized Health and Production of Poultry". Animals 12, n. 23 (1 dicembre 2022): 3378. http://dx.doi.org/10.3390/ani12233378.
Testo completoAbstract (sommario):
The poultry sector is facing infections from Salmonella, Campylobacter, Listeria and Staphylococcus spp., and Escherichia coli, that have developed multidrug resistance aptitude. Antibiotics cause disturbances in the balance of normal microbiota leading to dysbiosis, immunosuppression, and the development of secondary infections. Bacteriophages have been reported to lower the colonization of Salmonella and Campylobacter in poultry. The specificity of bacteriophages is greater than that of antibiotics and can be used as a cocktail for enhanced antibacterial activity. Specie-specific phages have been prepared, e.g., Staphylophage (used against Staphylococcus bacteria) that specifically eliminate bacterial pathogens. Bacteriophage products, e.g., BacWashTM and Ecolicide PX have been developed as antiseptics and disinfectants for effective biosecurity and biosafety measures. The success of phage therapy is influenced by time to use, the amount used, the delivery mechanism, and combination therapy with other therapeutics. It is a need of time to build a comprehensive understanding of the use of bacteriophages in poultry production. The current review thus focuses on mechanisms of bacteriophages against poultry pathogens, their applications in various therapeutics, impacts on the economy, and current challenges.
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Cha, Yoyeon, Jihwan Chun, Bokyung Son e Sangryeol Ryu. "Characterization and Genome Analysis of Staphylococcus aureus Podovirus CSA13 and Its Anti-Biofilm Capacity". Viruses 11, n. 1 (12 gennaio 2019): 54. http://dx.doi.org/10.3390/v11010054.
Testo completoAbstract (sommario):
Staphylococcus aureus is one of the notable human pathogens that can be easily encountered in both dietary and clinical surroundings. Among various countermeasures, bacteriophage therapy is recognized as an alternative method for resolving the issue of antibiotic resistance. In the current study, bacteriophage CSA13 was isolated from a chicken, and subsequently, its morphology, physiology, and genomics were characterized. This Podoviridae phage displayed an extended host inhibition effect of up to 23 hours of persistence. Its broad host spectrum included methicillin susceptible S. aureus (MSSA), methicillin resistant S. aureus (MRSA), local S. aureus isolates, as well as non-aureus staphylococci strains. Moreover, phage CSA13 could successfully remove over 78% and 93% of MSSA and MRSA biofilms in an experimental setting, respectively. Genomic analysis revealed a 17,034 bp chromosome containing 18 predicted open reading frames (ORFs) without tRNAs, representing a typical chromosomal structure of the staphylococcal Podoviridae family. The results presented here suggest that phage CSA13 can be applicable as an effective biocontrol agent against S. aureus.
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Gautam, Bikram, Lomas Aryal, Sachana Adhikari, Manoj Rana, Anjita Rajbhanshi, Sunita Ghale e Rameshwar Adhikari. "Isolation of Bacteriophage from Guheswori Sewage Treatment Plant Capable of Infecting Pathogens". Research in Pharmacy and Health Sciences 4, n. 2 (15 maggio 2018): 465–70. http://dx.doi.org/10.32463/rphs.2018.v04i02.11.
Testo completoAbstract (sommario):
Background: Waste water contains microorganisms which are continuously shed in the feces. These microorganisms especially bacteria might acquire antibiotic resistance and pose a significant threat to human health. Therefore, this work aims at isolating bacteriophage capable of infecting the isolated bacteria. Methodology: For this purpose, the grab sampling was performed at the Guheswori sewage treatment plant from the inlet in the primary treatment plant and from the outlet of the secondary treatment plant. For the isolation of bacteriophage, bacteriophage in the sewage was first enriched in an isolated pathogen, then filtered and then subjected to the isolates in the nutrient agar. Results: Pathogens like Escherichia coli, Salmonella Typhi, Enterococcus faecalis, Staphylococcus aureus, Coagulase negative Staphylococcus (CONS), Citrobacter fruendii, Enterobacter aerogenes, Proteus mirabilis, P. vulgaris, Pseudomonas aeruginosa were screened. Bacteriophage was able to infect E. coli (p < 0.001), S. Typhi (p < 0.001), E. faecalis (p = 0.182); and unable to infect S. aureus, CONS, C. fruendii, E. aerogenes, P. mirabilis, P. vulgaris, P. aeruginosa. Conclusion: Bacteriophage are able to infect and kill pathogens like E. coli, S. Typhi, E. faecalis and unable to infect S. aureus, CONS, C. fruendii, E. aerogenes, P. mirabilis, P. vulgaris, P. aeruginosa. Among all other reasons of lowering bacterial load, bacteriophages could also be one of the confounding factor. Such bacteriophage able to infect and undergo lytic cycle could be used in phage typing.
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Gordina, Ekaterina M., Svetlana A. Bozhkova e L. N. Smirnova. "Effects of bacteriophages on biofilms formed by Staphylococcus aureus isolated from patients with orthopedic infection". Clinical Microbiology and Antimicrobial Chemotherapy 24, n. 3 (2022): 283–88. http://dx.doi.org/10.36488/cmac.2022.3.283-288.
Testo completoAbstract (sommario):
Objective. To study effects of bacteriophages on biofilm formation and formed biofilm by S. aureus isolated from patients with orthopedic infection. Materials and Methods. A total of 50 clinical strains of S. aureus were tested. Species identification was performed by MALDI-TOF MS, antibiotic susceptibility – in accordance with the EUCAST v21. Isolates susceptibility to bacteriophages «Sextafag» (Microgen, Russia) was determined by MPA medium. The antibacterial activity of phages against S. aureus ATCC 29213 and S. aureus ATCC 43300 was evaluated by growth kinetic curves. Biofilms of bacteriophage-sensitive S. aureus strains were formed according to the protocol described by O’Toole. Isolates were divided into categories in accordance with the Stepanovic criteria. The effects of bacteriophages on the formation of S. aureus biofilm were studied by co-incubation of phages and bacteria followed by calculation of the percentage inhibition relative to the control without the introduction of the phages. The effect of phages on 24-hour biofilms formed by staphylococci was also evaluated in comparison with the control. Results. Out of 50 clinical S. aureus strains studied, 43 isolates (86%) were susceptible to phages, including 22 MSSA and 21 MRSA. All phage-susceptible cultures were characterized by biofilm-forming ability of varying degree: 28% – weak biofilm producer, 35% – moderate, 37% – strong. Inhibition of biofilm formation was determined in all tested MRSA strains, while in 73% of isolates the index of biofilm formation inhibition was more than 80%, which exceeded this indicator for MSSA by 2.5 times. In turn, the destruction of the formed biofilm under the action of the bacteriophage was 72% for all S. aureus. In 57% of MSSA strains, the decrease in biofilm biomass in comparison with the control was more than 80%, while this indicator was 2 times higher than for MRSA. Conclusions. The results demonstrated a high in vitro efficacy of bacteriophages against biofilm formation in S. aureus.
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Oduor, Joseph Michael Ochieng', Nyamongo Onkoba, Fredrick Maloba, Washingtone Ouma Arodi e Atunga Nyachieo. "Efficacy of lytic Staphylococcus aureus bacteriophage against multidrug-resistant Staphylococcus aureus in mice". Journal of Infection in Developing Countries 10, n. 11 (24 novembre 2016): 1208–13. http://dx.doi.org/10.3855/jidc.7931.
Testo completoAbstract (sommario):
Introduction: The use of bacteriophages as an alternative treatment method against multidrug-resistant bacteria has not been explored in Kenya. This study sought to determine the efficacy of environmentally obtained lytic bacteriophage against multidrug-resistant Staphylococcus aureus (MDRSA) bacterium in mice. Methodology: Staphylococcus aureus bacterium and S. aureus-specific lytic phage were isolated from sewage and wastewater collected within Nairobi County, Kenya. Thirty mice were randomly assigned into three groups: MDRSA infection group (n = 20), phage-infection group (n = 5), and non-infection group (n = 5). The MDRSA infection group was further subdivided into three groups: clindamycin treatment (8 mg/kg; n = 5), lytic phage treatment (108 PFU/mL (n = 5), and a combination treatment of clindamycin and lytic phage (n = 5). Treatments were done at either 24 or 72 hours post-infection (p.i), and data on efficacy, bacterial load, and animal physical health were collected. Results: Treatment with phage was more effective (100%) than with clindamycin (62.25% at 24 hours p.i and 87.5% at 72 hours p.i.) or combination treatment (75% at 24 hours p.i. and 90% at 72 hours p.i.) (p < 0.001). Conclusions: The results show that the environmentally obtained S. aureus lytic bacteriophage has therapeutic potential against MDRSA bacterium in mice.
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Imanishi, Ichiro, Jumpei Uchiyama, Toshihiro Tsukui, Junzo Hisatsune, Kaori Ide, Shigenobu Matsuzaki, Motoyuki Sugai e Koji Nishifuji. "Therapeutic Potential of an Endolysin Derived from Kayvirus S25-3 for Staphylococcal Impetigo". Viruses 11, n. 9 (22 agosto 2019): 769. http://dx.doi.org/10.3390/v11090769.
Testo completoAbstract (sommario):
Impetigo is a contagious skin infection predominantly caused by Staphylococcus aureus. Decontamination of S. aureus from the skin is becoming more difficult because of the emergence of antibiotic-resistant strains. Bacteriophage endolysins are less likely to invoke resistance and can eliminate the target bacteria without disturbance of the normal microflora. In this study, we investigated the therapeutic potential of a recombinant endolysin derived from kayvirus S25-3 against staphylococcal impetigo in an experimental setting. First, the recombinant S25-3 endolysin required an incubation period of over 15 minutes to exhibit efficient bactericidal effects against S. aureus. Second, topical application of the recombinant S25-3 endolysin decreased the number of intraepidermal staphylococci and the size of pustules in an experimental mouse model of impetigo. Third, treatment with the recombinant S25-3 endolysin increased the diversity of the skin microbiota in the same mice. Finally, we revealed the genus-specific bacteriolytic effect of recombinant S25-3 endolysin against staphylococci, particularly S. aureus, among human skin commensal bacteria. Therefore, topical treatment with recombinant S25-3 endolysin can be a promising disease management procedure for staphylococcal impetigo by efficient bacteriolysis of S. aureus while improving the cutaneous bacterial microflora.
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Horiuk, Y. "Determination of the drug Fagomast effectiveness with different titers of Phage SAvB14". Naukovij vìsnik veterinarnoï medicini, n. 2 (168) (9 dicembre 2021): 57–64. http://dx.doi.org/10.33245/2310-4902-2021-168-2-57-64.
Testo completoAbstract (sommario):
Treatment of bacterial infections with bacteriophages is one of the alternative methods. However, the use of freely dispersed bacteriophages for treatment causes their inactivation under physiological conditions. Therefore, it is important to consider the concentration of bacteriophages in phage therapy. The aim of study – to determine the optimal titer of bacteriophage Phage SAvB14 in the drug Fagomast for the effective treatment of subclinical mastitis in cows caused by Stapholococcus aureus var. bovis. For research to determine the optimal therapeutic dose of the bacteriophage drug Fagomast in vitro, groups of animals were formed on the principle of analogues. Controls were animals treated with an antibiotic-based drug according to the instructions for use. Cows of the first experimental group were used samples of the drug with a titer of Phage SAvB14 10-7 BFU/ml, the second experimental group with a titer of 10-8 BFU/ml and the third group – 10-9 BFU/ml. It was found that all batches of Fagomast (81.8 - 92.8%) show good therapeutic efficacy, but the duration of treatment of animals was different. When using the drug Fagomast with a phage titer of 10-9 BFU/ml, it is shorter by 1 day than cows that were injected with a phage titer of 10-8 BFU/ml and 1.5 days compared with cows of the first group, which were injected with a phage titer of 10-7 BFU/ml. The results of the therapeutic efficacy of Fagomast with a bacteriophage titer of 10-8 and 10-9 BFU/ml in the drug are confirmed by the reaction with Mastidine, which after 48 hours was assessed as doubtful, and after 72 hours – as negative, as with antibiotic treatment. The content of S. aureus in the secretion of cows 12 hours after administration of the drug with a phage titer of 10-9 BFU/ml decreased 6 times (P ≤ 0.05), and after 48 hours 40 times (P ≤ 0.05), and after 60 hours of therapy did not stand out at all. The titer of bacteriophages remained at the level of 10-7 BFU/ml, and when the number of susceptible bacteria decreased to zero it decreased by 2 orders of magnitude. Thus, it can be said that maintaining a higher concentration of phage virions leads to better distribution of phages in the breast, and thus to improved binding of phages to host cells and their destruction. Key words: bacteriophages, Staphylococcus aureus, phagotherapy, bacteriophage drug, mastitis, cows.
32
Aslanov, B. I., A. V. Lubimova e L. P. Zueva. "BACTERIOPHAGES AS EFFECTIVE ANTIEPIDEMIC AGENTS FOR CONTROL OF HOSPITAL-ACQUIRED INFECTION OUTBREAKS". Journal Infectology 11, n. 1 (30 marzo 2019): 65–70. http://dx.doi.org/10.22625/2072-6732-2019-11-1-65-70.
Testo completoAbstract (sommario):
Antibiotic resistance threatens the effective prevention and treatment of healthcare associated infections which are the most frequent adverse event in health-care settings worldwide. There is an urgent need to investigate alterative preventive and treatment options while there are still a few antibiotics left. Bacteriophage (phage) therapy has been championed as a promising alternative to antibiotics.The aim of this study was to evaluate the efficacy of a therapeutic bacteriophages to control of Staphylococcus aureus and Klebsiella pneumonia outbreaks in newborn intensive care units.Materials and methods. Commercial bacteriophage cocktails targeting these paphogens was orally and locally given over 5 days to patients of neonatal intensive care units in Saint-Petersburg, Russia.Results. Bacteriophages were used as antimicrobial agents for control of three S.aureus outbreaks and one K.pneumonia outbreak. S.aureus infection incidence during the three outbreaks were 22.2%, 54.5% and 50.0% accordingly, and K.pneumoniae outbreak – 19.0%. After application of the phage cocktails among newborns, the incidence of infections caused by S.aureus and K. pneumoniae decreased to zero. All treatments were well tolerated. No adverse events were reported.Conclusion. Presented results clearly demonstrate high efficiency of bacteriophages. Phages have several features that make them potentially attractive antibacterial agents. Bacteriopahges are highly specific and very effective in destroying targeted bacteria, have only minimally impact on health-protecting normal flora bacteria, safe and rapidly modifiable to combat the emergence of newly arising bacterial threats.
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Voronkova, Olga S., e Albert I. Vinnikov. "Fahotyp and Sensitivity to Medications Phage Film-Forming Strains Staphylococcus aureus, Isolated from Respiratory Tract". International Letters of Natural Sciences 51 (febbraio 2016): 1–5. http://dx.doi.org/10.18052/www.scipress.com/ilns.51.1.
Testo completoAbstract (sommario):
The study of biological properties of filmforming Staphylococcus aureus strains, including its sensitivity to bacteriophages, is one of the important tasks of laboratory diagnostic service that allows, if it necessary, choose an alternative treatment strategy and to establish the sources of strains. In the study of material from the nose and throat of 26 persons-volunteers the strains of S. aureus were selected. Among them 16 (61.5%) were able to form biofilms. Analysis of resistance to phages drugs of filmformation strains of S. aureus showed that 87.5% strains were sensitive the phages drugs "Piobacteriophage" and "Bacteriophage staphylococcal liquid". Phage type was identified for 9 (56.3%) strains. 64.3% of these strains were sensitive to the 1 phage from set, 21.4% – to 2 and 14.3% – 3 phages. It was determined that 77.8% strains were typed by phages from third group. For 1 strain detected simultaneous sensitivity to phages of 2 and 3 groups. With phage 81 (out of group phage) interacted 4 strains: 2 showed sensitivity only to him and another 2 were also susceptible to phage of third group.
34
Voronkova, Olga S., e Albert I. Vinnikov. "Fahotyp and Sensitivity to Medications Phage Film-Forming Strains <i>Staphylococcus aureus</i>, Isolated from Respiratory Tract". International Letters of Natural Sciences 51 (9 febbraio 2016): 1–5. http://dx.doi.org/10.56431/p-15g9r4.
Testo completoAbstract (sommario):
The study of biological properties of filmforming Staphylococcus aureus strains, including its sensitivity to bacteriophages, is one of the important tasks of laboratory diagnostic service that allows, if it necessary, choose an alternative treatment strategy and to establish the sources of strains. In the study of material from the nose and throat of 26 persons-volunteers the strains of S. aureus were selected. Among them 16 (61.5%) were able to form biofilms. Analysis of resistance to phages drugs of filmformation strains of S. aureus showed that 87.5% strains were sensitive the phages drugs "Piobacteriophage" and "Bacteriophage staphylococcal liquid". Phage type was identified for 9 (56.3%) strains. 64.3% of these strains were sensitive to the 1 phage from set, 21.4% – to 2 and 14.3% – 3 phages. It was determined that 77.8% strains were typed by phages from third group. For 1 strain detected simultaneous sensitivity to phages of 2 and 3 groups. With phage 81 (out of group phage) interacted 4 strains: 2 showed sensitivity only to him and another 2 were also susceptible to phage of third group.
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Григорова, Екатерина, Ekaterina Grigorova, Наталья Воропаева, Natalya Voropayeva, Ульяна Немченко, Ulyana Nemchenko, Елена Иванова et al. "RESPONSE SENSITIVITY TO BACTERIOPHAGES OF STAPHYLOCOCCUS AUREUS STRAINS ISOLATED FROM THE MICROBIOTA OF THE OROPHARYNX IN CHILDREN OF IRKUTSK". Acta biomedica scientifica 2, n. 5 (18 gennaio 2018): 65–69. http://dx.doi.org/10.12737/article_5a3a0dbfab5dc2.42779093.
Testo completoAbstract (sommario):
Dysbiotic disorders of the oropharynx takes one of the first places in the structure of morbidity worldwide. The aim
of the study was to determine the peculiarities of microbiocenosis of the oropharynx in children at different ages
and to assess the level of sensitivity of S. aureus strains to specific bacteriophages. Material for the study consisted of
84 smears from the oropharynx of children with inflammatory diseases of the upper respiratory tract (nasopharyngi-
tis, pharyngitis, tonsillitis, laryngitis (J00, J02, J03, J04 according to ICD-10). The biological material was distributed
depending on the age of the surveyed: the first group – children 3–6 years (n = 61) and the second age group – children
7–12 years (n = 23). Studies of the microflora of the oropharynx were performed according to standard methods. Isolated
microorganisms were identified by morphological, tinctorial, cultural and biochemical properties. The results were
evaluated in accordance with the Order of USSR Ministry of Health N 535 as of April 22, 1985. Specific lytic activity of
bacteriophages against S. aureus was determined using preparations of staphylococcal bacteriophage and polyvalent
pyobacteriophage Sexta. The sensitivity of strains of S. aureus to specific bacteriophages was assessed by the method
of «crosses», according to the guidelines. Statistical analysis was performed with the use of licensed applications Office
MS Excel 2007 for Windows 7 BioStat v. 5.0.1. 2008. Correlation analysis (Pearson method) was used. It has been shown
that with increasing age children in the oropharynx microbial density is increasing for indicators of both normoflora
(S. oralis), and of opportunistic microflora (S. ß-hemolytic, S. pyogenes, S. pneumoniae, bacteria Enterobacteriaceae),
especially of S. aureus (up to 74 %). Registration of sensitive strains of S. aureus in more than 70 % of cases in preschool
and school-aged children is evidence of the correctness of correction of the dysbiotic disorders of the oropharynx with
the use of bacteriophages of staphylococcus and Sexta.
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O'Flaherty, S., R. P. Ross, W. Meaney, G. F. Fitzgerald, M. F. Elbreki e A. Coffey. "Potential of the Polyvalent Anti-Staphylococcus Bacteriophage K for Control of Antibiotic-Resistant Staphylococci from Hospitals". Applied and Environmental Microbiology 71, n. 4 (aprile 2005): 1836–42. http://dx.doi.org/10.1128/aem.71.4.1836-1842.2005.
Testo completoAbstract (sommario):
ABSTRACT The increasing prevalence of antibiotic-resistant staphylococci has prompted the need for antibacterial controls other than antibiotics. In this study, a lytic bacteriophage (phage K) was assessed in vitro for its ability to inhibit emerging drug-resistant Staphylococcus aureus strains from hospitals and other species of Staphylococcus isolated from bovine infections. In in vitro inhibitory assays, phage K lysed a range of clinically isolated methicillin-resistant S. aureus (MRSA) strains, S. aureus with heterogeneous vancomycin resistance and vancomycin resistance, and teicoplanin-resistant strains. In these assays, 14 of the MRSA strains were initially only weakly sensitive to this phage. However, propagation of phage K on these less-sensitive strains resulted in all 14 being sensitive to the modified phages. The results enforce the principle that, while certain target bacteria may be relatively insensitive to lytic phage, this can be overcome by obtaining modified phage variants from passage of the phage through the insensitive strains. Model in situ hand wash studies using a phage-enriched wash solution resulted in a 100-fold reduction in staphylococcal numbers on human skin by comparison with numbers remaining after washing in phage-free solution. Infusion of the phage into a nonimmunogenic bismuth-based cream resulted in strong anti-Staphylococcus activity from the cream on plates and in broth.
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Kitamura, Naoya, Eri Sasabe, Shigenobu Matsuzaki, Masanori Daibata e Tetsuya Yamamoto. "Characterization of two newly isolated Staphylococcus aureus bacteriophages from Japan belonging to the genus Silviavirus". Archives of Virology 165, n. 10 (3 agosto 2020): 2355–59. http://dx.doi.org/10.1007/s00705-020-04749-6.
Testo completoAbstract (sommario):
Abstract Two Staphylococcus aureus bacteriophages, KSAP7 and KSAP11, were isolated from sewage and characterized. Based on morphology and DNA sequences, they were assigned to the genus Silviavirus, subfamily Twortvirinae, family Herelleviridae, whose members are hypothesized to be suitable for bacteriophage therapy. The KSAP7 and KSAP11 genomes were 137,950 and 138,307 bp in size, respectively. Although their DNA sequences were almost identical, evidence of site-specific DNA rearrangements was found in two regions. Changes in the number of PIEPEK amino acid sequence repeats encoded by orf10 and the insertion/deletion of a 541-bp sequence that includes a possible tail-related gene were identified.
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Speck, Peter G., Morgyn S. Warner, Shailesh Bihari, Andrew D. Bersten, James G. Mitchell, Joseph Tucci e David L. Gordon. "Potential for bacteriophage therapy for Staphylococcus aureus pneumonia with influenza A coinfection". Future Microbiology 16, n. 3 (febbraio 2021): 175–84. http://dx.doi.org/10.2217/fmb-2020-0163.
Testo completoAbstract (sommario):
The ability of influenza A virus to evolve, coupled with increasing antimicrobial resistance, could trigger an influenza pandemic with great morbidity and mortality. Much of the 1918 influenza pandemic mortality was likely due to bacterial coinfection, including Staphylococcus aureus pneumonia. S. aureus resists many antibiotics. The lack of new antibiotics suggests alternative antimicrobials, such as bacteriophages, are needed. Potential delivery routes for bacteriophage therapy (BT) include inhalation and intravenous injection. BT has recently been used successfully in compassionate access pulmonary infection cases. Phage lysins, enzymes that hydrolyze bacterial cell walls and which are bactericidal, are efficacious in animal pneumonia models. Clinical trials will be needed to determine whether BT can ameliorate disease in influenza and S. aureus coinfection.
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Pertics, Botond Zsombor, Dalma Szénásy, Dániel Dunai, Yannick Born, Lars Fieseler, Tamás Kovács e György Schneider. "Isolation of a Novel Lytic Bacteriophage against a Nosocomial Methicillin-Resistant Staphylococcus aureus Belonging to ST45". BioMed Research International 2020 (22 dicembre 2020): 1–10. http://dx.doi.org/10.1155/2020/5463801.
Testo completoAbstract (sommario):
Methicillin-resistant Staphylococcus aureus (MRSA) can cause a wide range of infections from mild to life-threatening conditions. Its enhanced antibiotic resistance often leads to therapeutic failures and therefore alternative eradication methods must be considered. Potential candidates to control MRSA infections are bacteriophages and their lytic enzymes, lysins. In this study, we isolated a bacteriophage against a nosocomial MRSA strain belonging to the ST45 epidemiologic group. The phage belonging to Caudovirales, Siphoviridae, showed a narrow host range and stable lytic activity without the emergence of resistant MRSA clones. Phylogenetic analysis showed that the newly isolated Staphylococcus phage R4 belongs to the Triavirus genus in Siphoviridae family. Genetic analysis of the 45 kb sequence of R4 revealed 69 ORFs. No remnants of mobile genetic elements and traces of truncated genes were observed. We have localized the lysin (N-acetylmuramoyl-L-alanine amidase) gene of the new phage that was amplified, cloned, expressed, and purified. Its activity was verified by zymogram analysis. Our findings could potentially be used to develop specific anti-MRSA bacteriophage- and phage lysin-based therapeutic strategies against major clonal lineages and serotypes.
40
González-Menéndez, Eva, Lucía Fernández, Diana Gutiérrez, Daniel Pando, Beatriz Martínez, Ana Rodríguez e Pilar García. "Strategies to Encapsulate the Staphylococcus aureus Bacteriophage phiIPLA-RODI". Viruses 10, n. 9 (13 settembre 2018): 495. http://dx.doi.org/10.3390/v10090495.
Testo completoAbstract (sommario):
The antimicrobial properties of bacteriophages make them suitable food biopreservatives. However, such applications require the development of strategies that ensure stability of the phage particles during food processing. In this study, we assess the protective effect of encapsulation of the Staphylococcus aureus bacteriophage phiIPLA-RODI in three kinds of nanovesicles (niosomes, liposomes, and transfersomes). All these systems allowed the successful encapsulation of phage phiIPLA-RODI with an efficiency ranged between 62% and 98%, regardless of the concentration of components (like phospholipids and surfactants) used for vesicle formation. Only niosomes containing 30 mg/mL of surfactants exhibited a slightly lower percentage of encapsulation. Regarding particle size distribution, the values determined for niosomes, liposomes, and transfersomes were 0.82 ± 0.09 µm, 1.66 ± 0.21 µm, and 0.55 ± 0.06 µm, respectively. Importantly, bacteriophage infectivity was maintained during storage for 6 months at 4 °C for all three types of nanovesicles, with the exception of liposomes containing a low concentration of components. In addition, we observed that niosomes partially protected the phage particles from low pH. Thus, while free phiIPLA-RODI was not detectable after 60 min of incubation at pH 4.5, titer of phage encapsulated in niosomes decreased only 2 log units. Overall, our results show that encapsulation represents an appropriate procedure to improve stability and, consequently, antimicrobial efficacy of phages for application in the food processing industry.
41
Wills, Quintin F., Claire Kerrigan e James S. Soothill. "Experimental Bacteriophage Protection against Staphylococcus aureus Abscesses in a Rabbit Model". Antimicrobial Agents and Chemotherapy 49, n. 3 (marzo 2005): 1220–21. http://dx.doi.org/10.1128/aac.49.3.1220-1221.2005.
Testo completoAbstract (sommario):
ABSTRACT In a rabbit model of wound infection caused by Staphylococcus aureus, 2 × 109 PFU of staphylococcal phage prevented abscess formation in rabbits when it was injected simultaneously with S. aureus (8 × 107 CFU) into the same subcutaneous site. Phage multiplied in the tissues. Phages might be a valuable prophylaxis against staphylococcal infection.
42
Fenton, Mark, Ruth Keary, Olivia McAuliffe, R. Paul Ross, Jim O'Mahony e Aidan Coffey. "Bacteriophage-Derived PeptidaseCHAPKEliminates and Prevents Staphylococcal Biofilms". International Journal of Microbiology 2013 (2013): 1–8. http://dx.doi.org/10.1155/2013/625341.
Testo completoAbstract (sommario):
New antibacterial agents are urgently needed for the elimination of biofilm-forming bacteria that are highly resistant to traditional antimicrobial agents. Proliferation of such bacteria can lead to significant economic losses in the agri-food sector. This study demonstrates the potential of the bacteriophage-derived peptidase,CHAPK, as a biocidal agent for the rapid disruption of biofilm-forming staphylococci, commonly associated with bovine mastitis. PurifiedCHAPKapplied to biofilms ofStaphylococcus aureusDPC5246 completely eliminated the staphylococcal biofilms within 4 h. In addition,CHAPKwas able to prevent biofilm formation by this strain. TheCHAPKlysin also reducedS. aureusin a skin decolonization model. Our data demonstrates the potential ofCHAPKas a biocidal agent for prevention and treatment of biofilm-associated staphylococcal infections or as a decontaminating agent in the food and healthcare sectors.
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Venezia, Richard A., Michael Orrico, Edward Houston, Shu-Min Yin e Yelena Y. Naumova. "Lethal Activity of Nonthermal Plasma Sterilization Against Microorganisms". Infection Control & Hospital Epidemiology 29, n. 5 (maggio 2008): 430–36. http://dx.doi.org/10.1086/588003.
Testo completoAbstract (sommario):
Objective.To determine the range and the mode of germicidal activity of sterilants generated by a nonthermal plasma sterilization system for microorganisms.Methods.Representative bacteria, spores, viruses, bacteriophages, and fungi were exposed to the plasma cycle and the residual viability was measured in vitro. To assess the mode of lethal injury,Escherichia coli, Staphylococcus aureus, Bacillus atrophaeus,and bacteriophages were exposed to the plasma cycle, and the effects of the plasma-generated sterilants on the biological parameters were determined.Results.There were at least 4-6 log reductions in viability for all microorganisms after 10 minutes of exposure to the plasma cycle. Electron micrographs and studies of the inhibition of bacteriophage infectivity suggested that the primary injury is to the organisms' cell envelopes. The plasma cycle also denatured isolated bacterial proteins and inactivated bacteriophages, but it had no effect on isolated DNA and bacterial proteins within exposed bacteria.Conclusion.Nonthermal plasma, which is produced at atmospheric temperature and pressure, generates sterilants that kill high concentrations of microorganisms and inactivate viruses during a 10-minute exposure. The primary injury appears to be at the surface structures of the organisms. This suggests that nonthermal plasma has utility for sterilization of heat-sensitive medical materials and devices.
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Zhandalgarova, Adelya Dzumaniyashevna, Anna Aleksandrovna Bakhareva, Yulia Nikolaevna Grozesku e Aleksandr Nevalennyy. "Study of microbiocenosis of fish gills and intestines in their cultivation using preparations based on bacteriophages". Vestnik of Astrakhan State Technical University. Series: Fishing industry, n. 4 (30 dicembre 2021): 126–33. http://dx.doi.org/10.24143/2073-5529-2021-4-126-133.
Testo completoAbstract (sommario):
Nowadays bacteriophages are widely used in veterinary medicine, bio-technology, agriculture and in particular in aquaculture. Narrow specificity affecting the bacterial microflora and selective influence on the pathogenic and opportunistic microorganisms allow using the bacteriophages for diagnosing, preventing and treating the diseases of farm animals and fish. The emergence of antibiotic-resistant strains of microorganisms involves the search for new drugs to combat them. In this regard, phage therapy is an alternative to antimicrobial treatment of bacterial diseases of animals and fish. Despite the lack of data on the bacteriophage-based drugs applications in aquaculture, this direction is found to be promising and relevant. There is given a comparative analysis of the microbiocenosis of the gills and intestines of two-year-olds of red tilapia farmed in the water with adding the poly-valence pyobacteriophage and fed by compound feed treated by the preparation. It has been found that the dominant position in the intestinal microbiocenosis of red tilapia belongs to Micrococcus bacteria, whose share made 45.7% of all isolates of the gastrointestinal tract.
By the frequency of occurrence, the second place is taken by the Bacterium species (33.2%), the third place - Staphylococcus (16.1%) species. The remaining groups of intestinal microorganisms are presented by a significantly number of isolates. It has been stated that the gills microflora was represented by a smaller species composition compared to the digestive tract microbiota. Isolates of the Bacterium and Staphylococcus bacteria were dominating, while the Actinomycetales and Bacillus microorganisms were represented in smaller numbers (1-2 colonies). The addition of a bacteriophage to water and its processing of compound feed helps to reduce the contamination of gills and reduce pathogenic microflora in the intestines of fish.
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Horiuk, Y. V., M. D. Kukhtyn, V. V. Horiuk, V. A. Sytnik e O. O. Dashkovskyy. "Effect of Phage SAvB14 combined with antibiotics on Staphylococcus aureus variant bovis". Regulatory Mechanisms in Biosystems 12, n. 3 (3 settembre 2021): 531–36. http://dx.doi.org/10.15421/022173.
Testo completoAbstract (sommario):
Because using antimicrobial drugs leads to development of resistance among bacterial isolates, the treatment with antimicrobial drugs in human and veterinary medicine in general should be reduced. Currently, therapeutic use of bacteriophages may be an alternative or addition to the treatment of bacterial infections of animals. The article presents the results of studying the effect of bacteriophage Phage SAvB14 on microbial biofilms of Staphylococcus aureus variant bovis both alone and in complex with antibiotics. For this purpose, we used strain S. aureus var. bovis 1491 f and bacteriophage Phage SAvB14, isolated at dairy farms. The effect of combined application of phage and antibiotics (gentamicin, tetracycline, сeftriaxone and enrofloxacin) were assessed after simultaneous and subsequent introduction of Phage SAvB14 in the dose of 105 plaque-forming units per milliliter (PFU/mL) and corresponding concentrations of antibiotics to 24h biofilms. We determined that of the tested antibiotics, only gentamicin and ceftriazone exerted synergic effects in combinations with Phage SAvB14. Combination treatment using gentamicin and the phage decreased the amount of S. aureus in biofilm by 39.81 times compared with the phage-only treatment. Significant synergic effect was also taken by ceftriaxone – it killed 1.26 times more bacteria in combination with the phage than alone. Other antibiotics did not increase antibiotic activity of the phage. Specifically, 1.11 and 1.26 times more vital cells remained after the actions of tetracycline and enrofloxacin than after the exposure to the bacteriophage only. Therefore, the obtained results indicate that biofilm of S. aureus var. bovis may be eliminated using Phage SAvB14 as an individual antibacterial agent, as well as in complex with antibiotics. However, complex treatment would imply introducing the phage and then antibiotic some time later.
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Horiuk, Yu V. "Characterization of the biological properties of bacteriophages Staphylococcus aureus variant bovis". Scientific Messenger of LNU of Veterinary Medicine and Biotechnologies 21, n. 96 (14 dicembre 2019): 47–52. http://dx.doi.org/10.32718/nvlvet9608.
Testo completoAbstract (sommario):
Cattle mastitis is the main cause of economic losses in milk production worldwide, and Staphylococcus aureus is the pathogen that causes it most. Bacteriophages may be an alternative treatment for this disease. In this study, we studied the effect of temperature and pH on the lytic activity of bacteriophages isolated from cows with signs of mastitis. The isolation and production of pure phage lines were performed on an indicator culture of Staphylococcus aureus var. bovis 1491f conventional methods. The following phages were isolated and labeled: Phage SAvB07, Phage SAvB08, Phage SAvB12, Phage SAvB14. To determine the effect of temperature and pH, aliquots after the action of these factors were sown by the double agar method at regular intervals. The study found that phage lytic activity was temperature dependent. Thus, under the influence of temperature 45 °C after 30 minutes of action, it decreased by 3.0–3.4 times for bacteriophages Phage SAvB07, Phage SAvB08, Phage SAvB12 and after one hour was 2.4–12.6%. Phage SAvB14 strain was more resistant to temperature. Its activity decreased by only 67.6% during the analyzed period. With higher temperatures (55–65 °C), the intensity of phage infection decreased significantly, but remained stable. The most resistant to the effects of temperature was Phage SAvB14 – its activity was on average higher by 15.6–33.9% compared with other phages taken in the experiment. The results of our studies on the effect of pH on the reproduction of phages showed that the maximum number of phage virions was observed at pH 6 7. However, the most resistant to acidity was the phage strain Phage SAvB14, compared with other strains taken in the experiment. Therefore, the bacteriophage Phage SAvB14 exhibited the greatest stability and has considerable potential for in vivo use in the treatment of mastitis of cows caused by Staphylococcus aureus.
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Das, Avijit, Sukhendu Mandal, Vijay Hemmadi, Vivek Ratre e Malabika Biswas. "Studies on the gene regulation involved in the lytic–lysogenic switch in Staphylococcus aureus temperate bacteriophage Phi11". Journal of Biochemistry 168, n. 6 (23 luglio 2020): 659–68. http://dx.doi.org/10.1093/jb/mvaa080.
Testo completoAbstract (sommario):
Abstract Antirepressor proteins of bacteriophages are chiefly involved in interfering with the function of the repressor protein and forcing the bacteriophage to adopt the lytic cycle. The genome of Staphylococcus aureus phage, Phi11 has already been sequenced; from the genome sequence, we amplified gp07 gene and analysed its involvement in the developmental pathway of Phi11. Our results indicate that Gp07 functions as a novel antirepressor and regulates the developmental pathway of Phi11 by enhancing the binding of the Cro repressor protein to its cognate operator. We also report our finding that the CI repressor protein of Phi11 binds to the putative operator of Gp07 and regulates its expression. We further report that S.aureus transcriptional repressor LexA and coprotease RecA play a crucial role in the lytic–lysogenic switching in Phi11. We also identified that the N-terminal domain (Bro-N) of Gp07 is actually responsible for enhancing the binding of Cro repressor to its cognate operator. Our results suggest that Phi11 prophage induction is different from other bacteriophages. This study furnishes a first-hand report regarding the regulation involved in the developmental pathway of Phi11.
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Abril, Ana G., Mónica Carrera, Karola Böhme, Jorge Barros-Velázquez, Benito Cañas, José-Luis R. Rama, Tomás G. Villa e Pilar Calo-Mata. "Proteomic Characterization of Bacteriophage Peptides from the Mastitis Producer Staphylococcus aureus by LC-ESI-MS/MS and the Bacteriophage Phylogenomic Analysis". Foods 10, n. 4 (8 aprile 2021): 799. http://dx.doi.org/10.3390/foods10040799.
Testo completoAbstract (sommario):
The present work describes LC-ESI-MS/MS MS (liquid chromatography-electrospray ionization-tandem mass spectrometry) analyses of tryptic digestion peptides from phages that infect mastitis-causing Staphylococcus aureus isolated from dairy products. A total of 1933 nonredundant peptides belonging to 1282 proteins were identified and analyzed. Among them, 79 staphylococcal peptides from phages were confirmed. These peptides belong to proteins such as phage repressors, structural phage proteins, uncharacterized phage proteins and complement inhibitors. Moreover, eighteen of the phage origin peptides found were specific to S. aureus strains. These diagnostic peptides could be useful for the identification and characterization of S. aureus strains that cause mastitis. Furthermore, a study of bacteriophage phylogeny and the relationship among the identified phage peptides and the bacteria they infect was also performed. The results show the specific peptides that are present in closely related phages and the existing links between bacteriophage phylogeny and the respective Staphylococcus spp. infected.
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Turdieva, Sh T., G. R. Nasirova e D. K. Ganiyeva. "Possibilities of inhalation bacteriophage therapy in treatment of children with acute tonsillitis". Meditsinskiy sovet = Medical Council, n. 17 (1 novembre 2021): 86–93. http://dx.doi.org/10.21518/2079-701x-2021-17-86-93.
Testo completoAbstract (sommario):
Introduction. At the same time, in the last decade, pediatricians have increased interest in the study of the therapeutic effect of bacteriophages in infectious diseases of rhinolaryngological organs.Objective. The analysis of results of the use of inhalation bacteriophage therapy in children with acute tonsillitis, on an outpatient basis.Materials and methods. Examined 212 children from 4 to 15 years old with acute tonsillitis. Conducted general clinical research, pharyngoscopy, bacteriological examination of a smear of tonsils. Bacteriophage therapy carried out using the Pyobacteriophage complex liquid (PCL).Results. In the course of an objective clinical analysis, on the day of seeking outpatient care, patients noted asthenovegetative disorders in all patients (100%), in the form of general weakness (96.8%), loss of appetite (94.8%), and headache (92.5%). During the examination, cervical lymphadenopathy (98.6%), tonsil hyperemia and hyperplasia (98.1%), and exudates (48.1%) noted. It revealed that the main causative agents of acute tonsillitis in children were the bacteria Streptococcus pyogenes, Staphylococcus aureus, Streptococcus pneumoniae and Haemophilus influenzae, with different relative proportions (from 24.2% to 59%). Inhalation bacteriophage therapy carried out from the first days of the disease. Against the background of therapy, it was noted - a decrease in swelling in the tonsils by 2-3 days with a decrease in general intoxication signs. On the 6th day from the beginning of bacteriophage therapy, asthenovegetative disorders stopped 2.2 times faster in relation to patients who did not receive bacteriophage therapy, against the background of a decrease in the manifestation of objective clinical signs of the disease.Conclusion. The use of inhalation bacteriophage therapy as part of the conservative treatment of acute tonsillitis in children contributes 1.4 times to the fastest relief of the acute period and an improvement in the subjective assessment of well-being is 25% higher concerning the comparison group.
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Pacífico, Hilbert, Sofka, Dinhopl, Pap, Aspöck e Hilbert. "Characterization of Bacteria and Inducible Phages in an Intensive Care Unit". Journal of Clinical Medicine 8, n. 9 (10 settembre 2019): 1433. http://dx.doi.org/10.3390/jcm8091433.
Testo completoAbstract (sommario):
Intensive care units (ICUs) are critical locations for the transmission of pathogenic and opportunistic microorganisms. Bacteria may develop a synergistic relationship with bacteriophages and more effectively resist various stresses, enabling them to persist despite disinfection and antimicrobial treatment. We collected 77 environmental samples from the surroundings of 12 patients with infection/colonizations by Escherichia coli, Staphylococcus aureus or Klebsiella spp in an ICU in Austria. Surface swabs were tested for lytic phages and bacterial isolates for mitomycin C-inducible prophages. No lytic bacteriophages were detected, but S. aureus was isolated from the surroundings of all patients. About 85% of the colonies isolated from surface samples were resistant to antimicrobials, with 94% of them multidrug resistant. Two inducible temperate bacteriophages—myovirus vB_EcoM_P5 and siphovirus vB_SauS_P9—were recovered from two clinical isolates. Staphylococci phage vB_SauS_P9 lysed S. aureus isolates from the surface swabs collected from the surroundings of three patients. No transductants were obtained on propagation in phage-sensitive antimicrobial-resistant isolates. The two phages were sensitive to 0.25% (v/v) of the disinfectant TPH Protect, which eliminated viable phages after 15 min. Coliphage vB_EcoM_P5 was inactivated at 70 °C and staphylococci phage vB_SauS_P9 at 60 °C after 60 min.