Bibliografias temáticas / Pathogenic bacteria

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Literatura científica selecionada sobre o tema "Pathogenic bacteria"

Autor: Grafiati

Publicado: 4 de junho de 2021

Última modificação: 1 de agosto de 2024

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Artigos de revistas sobre o assunto "Pathogenic bacteria"

Gvozdyak, R. I. "«Pathogen-1» Experiment Aggression of pathogenic bacteria in microgravity". Kosmìčna nauka ì tehnologìâ 6, n.º 4 (30 de julho de 2000): 111. http://dx.doi.org/10.15407/knit2000.04.119.

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Gaminda, K. A. P. "DEOXYRIBOZYMES IN DETECTION OF PATHOGENIC BACTERIA". Biotechnologia Acta 14, n.º 5 (outubro de 2021): 5–20. http://dx.doi.org/10.15407/biotech14.05.005.

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Aim. The purpose of the review was to analyze the use of DNAzyme biosensors for the detection of pathogens. In the recent years, deoxyribozymes (DNAzymes) have a significant impact as biosensors in diverse fields, from detection of metal ions in the environment to theranostic applications and detection of microorganisms. Although routinely used sophisticated instrumental methods are available to detect pathogenic bacterial contamination, they involve time-consuming, complicated sample pre-treatment and expensive instruments. As an alternative, pathogen-specific DNAzymes have demonstrated a series of advantages: a non-destructive rapid analysis technique with in situ and real-time detection of bacteria with high sensitivity and selectivity. A wide range of pathogen-specific DNAzymes has been developed using colorimetric and fluorescence-based detections for pathogenic bacterial contamination in various samples. The current review summarizes the in vitro selection of pathogen-specific DNAzymes, various strategies utilized in the sensor designs, and their potential use in theranostic applications.

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Harborne, Jeffrey B. "Plant pathogenic bacteria". Phytochemistry 27, n.º 5 (janeiro de 1988): 1569–70. http://dx.doi.org/10.1016/0031-9422(88)80251-6.

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Sabra, Sherifa. "Elimination Virulent-pathogenic-biofilm Bacteria Using Highland-wild Salvia officinalis Preserve Bacterial-infection-control". Biotechnology and Bioprocessing 2, n.º 2 (2 de fevereiro de 2021): 01–04. http://dx.doi.org/10.31579/2766-2314/021.

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This work for this title "Elimination Virulent-pathogenic-biofilm (VPB) Bacteria Using Highland-wild (HLW) Salvia officinalis (S. officinalis) Preserve Bacterial-infection-control (BIC)"; the aim was to prove the importance of HLW S. officinalis extracts have therapeutic herbal importance. Through its effected on the isolated VPB bacteria caused infection diseases that may preserve BIC for individuals, which proved the effectiveness of the HLW S. officinalis daily use or therapeutic use. S. officinalis specimens were collected during the flowering period from HLW, Taif, KSA. Essential oils (EOs) were equipped and biofilms preparation, then laboratory methods deputy for anti-biofilms formation activity and biofilms elimination activity, finally biofilms metabolic grades measurement. The bacterial metabolic grades of anti-biofilms formation activity showed the HLW S. officinalis EOs extracts eliminated VPB bacteria and effects were greater. Anywhere Staphylococcous aureus (S. aureus) and Streptococcus pyogenes (S. pyogenes) were eliminated until 60 hours. While Pseudomonas aeruginosa (PA) was eliminated at 72 hours. The bacterial metabolic grades of biofilms elimination activity found the HLW S. officinalis EOs extracts eliminated within 8 hours (S. aureus and S. pyogenes), PA was to 10 hours. Concluded the HLW S. officinalis EOs extracts had proven its ability to eliminate VPB bacteria, and from that, it proven on the type used with healthy characteristics to maintain health and BIC. Recommendation: That topic recommend using the appropriate HLW S. officinalis EOs extracts for individuals daily to maintain the general health. In cases of illness, person must ask the "Specialized Physician" to determine the healthy and curative amount to use.

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Al-Terehi, Mona, Saadi Shershab, Hadeel Alaa Al-Rrubaei e Ali H. Al-Saadi. "Some Oral Pathogenic Bacteria, Isolation and Diagnosis". Journal of Pure and Applied Microbiology 12, n.º 3 (30 de setembro de 2018): 1495–98. http://dx.doi.org/10.22207/jpam.12.3.54.

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Khan, Fazlurrahman, Sandra Folarin Oloketuyi e Young-Mog Kim. "Diversity of Bacteria and Bacterial Products as Antibiofilm and Antiquorum Sensing Drugs Against Pathogenic Bacteria". Current Drug Targets 20, n.º 11 (22 de agosto de 2019): 1156–79. http://dx.doi.org/10.2174/1389450120666190423161249.

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The increase in antibiotic resistance of pathogenic bacteria has led to the development of new therapeutic approaches to inhibit biofilm formation as well as interfere quorum sensing (QS) signaling systems. The QS system is a phenomenon in which pathogenic bacteria produce signaling molecules that are involved in cell to cell communication, production of virulence factors, biofilm maturation, and several other functions. In the natural environment, several non-pathogenic bacteria are present as mixed population along with pathogenic bacteria and they control the behavior of microbial community by producing secondary metabolites. Similarly, non-pathogenic bacteria also take advantages of the QS signaling molecule as a sole carbon source for their growth through catabolism with enzymes. Several enzymes are produced by bacteria which disrupt the biofilm architecture by degrading the composition of extracellular polymeric substances (EPS) such as exopolysaccharide, extracellular- DNA and protein. Thus, the interference of QS system by bacterial metabolic products and enzymatic catalysis, modification of the QS signaling molecules as well as enzymatic disruption of biofilm architecture have been considered as the alternative therapeutic approaches. This review article elaborates on the diversity of different bacterial species with respect to their metabolic products as well as enzymes and their molecular modes of action. The bacterial enzymes and metabolic products will open new and promising perspectives for the development of strategies against the pathogenic bacterial infections.

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Erlinawati, Erlinawati, e Safridha Kemala Putri. "Identifikasi bakteri patogen pada jajanan telur gulung yang dijual di Kecamatan Syiah Kuala Banda Aceh". Jurnal SAGO Gizi dan Kesehatan 4, n.º 1 (14 de dezembro de 2022): 58. http://dx.doi.org/10.30867/gikes.v4i1.1061.

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Background: Pathogenic bacteria can be a significant cause of food poisoning. Bacterial growth in food can also cause undesirable physical or chemical changes, making the food unfit for consumption. Egg roll is a snack easily found in Banda Aceh City, which children and adults generally consume. Snacks that contain high bacteria are very dangerous for health.Objectives: This study aims to determine the types of pathogenic bacteria in egg rolls sold in Syiah Kuala District, Banda Aceh.Methods: This experimental study was conducted in Syiah Kuala District, Banda Aceh City, 2020. Five samples were taken for bacterial examination at the Microbiology Laboratory, Medical Technology Poltekkes Kemenkes Aceh. Bacterial identification on egg rolls was observed for four days. Data analysis was only done descriptively.Results: The study identifying pathogenic bacteria on egg rolls showed that the egg roll samples were contaminated with several harmful bacteria. The bacterial colonies varied from the lowest distribution of 453,333 to the highest of 1,150,000. The bacteria were Citrobacter freundii, Proteus mirabilis, and pathogenic bacteria Salmonella sp.Conclusion: Egg rolls sold on the roadside have been contaminated with bacteria. The bacteria identified were Citrobacter freundii, Proteus mirabilis, and pathogenic bacteria Salmonella sp. Suggestions and efforts are needed from the authorities to conduct health promotion and training for egg roll sellers to maintain hygiene and sanitation of both tools and places of sale.

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Rezaeianaran, Farzad, e Martin A. M. Gijs. "Difference in Intestine Content of Caenorhabditis elegans When Fed on Non-Pathogenic or Pathogenic Bacteria". Micromachines 14, n.º 7 (7 de julho de 2023): 1386. http://dx.doi.org/10.3390/mi14071386.

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We investigated the bacterial food digestion and accumulation in wild-type adult Caenorhabditis elegans (C. elegans) worms that have fed on either non-pathogenic RFP-expressing Escherichia coli (E. coli) OP50 or pathogenic-RFP-expressing Pseudomonas aeruginosa (P. aeruginosa) PAO1 during the first 4 days of adulthood. Once the worms had completed their planned feeding cycles, they were loaded on microfluidic chips, where they were fixed to allow high-resolution z-stack fluorescence imaging of their intestines utilizing a Spinning Disk Confocal Microscope (SDCM) equipped with a high-resolution oil-immersion objective (60×). IMARIS software was used to visualize and analyze the obtained images, resulting in the production of three-dimensional constructs of the intestinal bacterial load. We discovered two distinct patterns for the bacteria-derived fluorescence signal in the intestine: (i) individual fluorescent spots, originating from intact bacteria, were present in the fluorescent E. coli-OP50-fed worms, and (ii) individual fluorescent spots (originating from intact bacteria) were dispersed in large regions of diffuse fluorescence (RDF), originating from disrupted bacteria, in fluorescent P. aeruginosa-PAO1-fed worms. We performed a semi-automated single-worm-resolution quantitative analysis of the intestinal bacterial load, which showed that the intestinal bacterial load generally increases with age of the worms, but more rapidly for the fluorescent P. aeruginosa-PAO1-fed worms.

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Asbury, Rachel, Erica Dipede e Bradley Saville. "Prebiotic Mannan-Oligosaccharides and Their Role in the Gut Microbiota". Current Developments in Nutrition 6, Supplement_1 (junho de 2022): 1130. http://dx.doi.org/10.1093/cdn/nzac072.002.

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Abstract Objectives Pathogenic bacterial infections in the gastrointestinal tract compromise the health and function of the gut microbiome, and the rising incidence of antibiotic-resistant bacterial strains has resulted in initiatives seeking alternative treatments. Some prebiotic fibers, such as mannan-oligosaccharides (MOS), may be a promising alternative. In addition to selectively growing commensal bacteria and creating a diverse gut microbiota, MOS have a high affinity for specific binding arms on the structure of some pathogenic bacteria and can prevent bacterial adhesion to intestinal epithelial cells. The ability of MOS to bind pathogenic bacteria and selectively grow commensal bacteria is influenced by its carbohydrate structure. However, there are no published studies to our knowledge on the optimization of MOS structure for both pathogen binding and commensal bacterial growth. Therefore, the focus of this work is to (1) assess the effectiveness of MOS on in vitro agglutination of various pathogenic bacterial species and, (2) explore the impact of MOS carbohydrate structure on pathogen binding. Methods Characterization of MOS will be performed using high performance liquid chromatography (HPLC) and liquid chromatography mass spectrometry (LCMS). To assess the ability of MOS to bind pathogenic bacteria, in vitro agglutination and growth inhibition assays will be performed. Prebiotic performance of MOS on commensal bacterial growth will be assessed using in vitro mixed culture analyses of both commensal and pathogenic bacterial species. Results Protocol Abstract Conclusions This research will inform further investigations of the ability of prebiotics such as MOS to support intestinal health through the selective growth of commensal bacteria and binding of pathogenic bacteria, as a nutritional supplement and as an alternative to antibiotics. Funding Sources Natural Sciences and Engineering Research Council of Canada.

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Linggarjati, Shiwi, Dita Diana Parti e Elly Nurus Sakinah. "Antibiotic sensitivity on pathogenic bacteria causing bacterial vaginosis". Majalah Obstetri & Ginekologi 29, n.º 1 (28 de abril de 2021): 18. http://dx.doi.org/10.20473/mog.v29i12021.18-22.

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Objectives: To identify the sensitivity of antibiotics to pathogenic bacteria that cause Bacterial Vaginosis (BV).Materials and Methods: This type of research was an observational study with a sample of six specimens. The data were taken using primary data from patients who were swabbed in the vagina and then diagnosed BV with amsel criteria on vaginal secretion specimens carried out at Tanggul health center on January 23-February 23, 2020. The specimens were sent to Parahita Clinical Laboratory for bacterial identification and adjusted for sensitivity with CLSI using vitek 2 compact tool.Results: The results of this study identified the bacteria that caused bacterial vaginosis, the E. coli and K. pneumoniae with one sample of suspected ESBL. ESBL is a beta lactamase enzyme produced by bacteria and can induce bacterial resistance to penicillin, cephalosporin generation 1, 2, and 3. The types of bacteria found were E. coli and K. pneumoniae with high sensitivity antibiotics tested including piperacillin/tazobactam, ceftazidime, cefepime, ertapenem, meropenem, amikacin, gentamicin, tigecycline, and nitrofurantoin. Antibiotics with high levels of resistance tested against these bacteria included: ampicillin, amoxicillin, and ampicillin/sulbactam due to the mechanism of beta-lactam antibiotic resistance in the production of beta lactamase from bacteria.Conclusion: The type of bacteria found was E. coli and K. pneumoniae with high resistance levels in beta lactam antibiotics.

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Teses / dissertações sobre o assunto "Pathogenic bacteria"

Château, Maarten de. "Functional, structural and evolutionary studies on a family of bacterial surface proteins". Lund : Dept. of Cell and Molecular Biology, Lund University, 1996. http://catalog.hathitrust.org/api/volumes/oclc/38947242.html.

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Kearney, Theresa Elizabeth. "Survival of pathogenic bacteria in anaerobic digesters". Thesis, Queen's University Belfast, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334706.

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Kim, Hyung Joo. "Electrochemical detection and enumeration of pathogenic bacteria". Thesis, King's College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244045.

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Salmon, Richard Michael. "Structural studies on proteins from pathogenic bacteria". Thesis, University of Sheffield, 2012. http://etheses.whiterose.ac.uk/3287/.

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Davids, Wagied. "Causes of Substitution Frequency Variation in Pathogenic Bacteria". Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4838.

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Lövkvist, Lena. "Receptor Interactions Between Pathogenic Bacteria and Host Cells". Doctoral thesis, Uppsala University, Department of Medical Biochemistry and Microbiology, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7782.

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This thesis focuses on host and pathogen specific interactions during invasive disease. We have investigated the role and impact of different virulence factors of Neisseria gonorrhoeae, N. meningitidis and Streptococcus pyogenes on host epithelial cells and in vivo.

N. gonorrhoeae cause the sexually transmitted disease gonorrhoea and N. meningitidis is the most common cause of bacterial meningitis and may be leathal to the host within hours of infection. The neisserial type IV pili were shown to have an important impact on host cells for the induction of pro-inflammatory and other cellular defence transcriptional responses. Furthermore, N. meningitidis generally induced an earlier response compared to N. gonorrhoeae, probably as a result of the meningococcal capsule. The role of N. meningitidis serogroup B lipooliogsaccharide was investigated during invasive disease. Bacterial invasion of host cells and blood survival as well as virulence in vivo was dependent on the integrity of the LOS structure.

S. pyogenes may cause a variety of diseases ranging from uncomplicated diseases such as 'strep-throat' to more severe invasive diseases such as necrotizing fasciitis and streptococcal toxic shock syndrome. S. pyogenes ScpC protease degrade interleukin 8 during necrotizing fasciitis. We investigated the role of ScpC in systemic disease and observed enhanced virulence by bacteria unable to degrade IL-8. Following an intravenous infection of mice pro-inflammatory cytokines and complement activation was induced by the ScpC negative mutant compared to the wild-type and correlated with higher bacteremia. These data indicate that the precense of the ScpC protease has an important impact on the host for the outcome of streptococcal sepsis. Another phagocytic escape mechanism of S. pyogenes is their ability to coat themselves with host proteins. We observed that released complement control protein, CD46, bound to the streptococcal cell surface. CD46 has been shown to interact with the streptococcal M protein and have now been found to bind to the surface of the bacteria in a growth phase dependent manner. We observed a more aggressive disease development in CD46 transgenic mice after an intravenous infection with an M6 serotype, resulting in higher mortality of CD46 transgenic mice compared with control mice. These data indicate that CD46 may confer a protection to the streptococci during early stage of systemic infection and contributes to the understanding of immune evsion of S. pyogenes.

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Abd, Hadi. "Interaction between waterborne pathogenic bacteria and Acanthamoeba castellanii /". Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-569-0/.

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Lövkvist, Lena. "Receptor interactions between pathogenic bacteria and host cells /". Uppsala : Acta Universitatis Upsaliensis : Uppsala universitetsbibliotek [distributör], 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7782.

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Chan, Anson Chi-Kit. "Iron transport in two pathogenic Gram-negative bacteria". Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/32406.

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Campylobacter jejuni and Escherichia coli strain F11 are two Gram-negative pathogens with a versatile armament of iron uptake systems to cope with the fluctuating host nutrient environment. Our current understanding of Gram-negative iron uptake systems focuses heavily on a prototypical scheme involving a TonB-dependent outer membrane receptor and an ABC transporter, with little knowledge on systems that do not fall neatly into this paradigm. The primary focus of this thesis is the characterization of three such atypical iron uptake proteins from C. jejuni (ChaN and P19) and pathogenic E. coli (FetP). C. jejuni ChaN is a 30 kDa, iron-regulated lipoprotein hypothesized to be involved in iron uptake. The crystal structure of ChaN reveals that it can bind two cofacial heme groups in a pocket formed by a ChaN dimer. Each heme iron is coordinated by a single tyrosine from one monomer and the propionate groups are hydrogen bonded by a histidine and a lysine from the other monomer. Analytical ultracentrifugation studies demonstrate heme-dependent dimerization in solution. Cell fractionation of C. jejuni shows that ChaN is localized to the outer membrane. Based on these findings, the predicted in vivo role of ChaN in iron uptake is discussed. C. jejuni cFtr1-P19 and E. coli FetMP are homologous iron-regulated systems also proposed to be iron transporters. Through growth studies in both organisms, we show that P19 and FetMP are required for optimal growth under iron-limited conditions. Furthermore, metal binding analysis demonstrates that recombinant P19 and FetP bind both copper and iron. Dimerization of P19 is shown to be metal dependent in vitro and is detected in vivo by cross-linking. Through x-ray crystallography, we have determined the structures of P19 and FetP with various metals bound, thus revealing the locations of the highly conserved copper and iron binding sites. Additionally, the crystal structure of FetP reveals two copper positions in each binding site that is likely functionally important. Through mutagenesis, residues contributing to the alternative copper positions were identified. Together, these studies provide insight into the mechanism of iron transport by the two systems and allow for the development of functional models.

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Hitchen, Paul Gareth. "Structural analysis of lipo-oligosaccharides from pathogenic bacteria". Thesis, Imperial College London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268463.

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Mais fontes

Livros sobre o assunto "Pathogenic bacteria"

Civerolo, E. L., A. Collmer, R. E. Davis e A. G. Gillaspie, eds. Plant Pathogenic Bacteria. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3555-6.

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De Boer, Solke H., ed. Plant Pathogenic Bacteria. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-010-0003-1.

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A, Pietrowski R., ed. Bacterial toxins. 2^a ed. Wokingham: Van Nostrand Reinhold, 1986.

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Kidd, Stephen P. Stress response in pathogenic bacteria. Wallingford, Oxfordshire, UK: CABI, 2011.

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Wang, Nian. Virulence mechanisms of plant-pathogenic bacteria. St. Paul, Minnesota: American Phytopathological Society, 2015.

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Kidd, S. P., ed. Stress response in pathogenic bacteria. Wallingford: CABI, 2011. http://dx.doi.org/10.1079/9781845937607.0093.

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Bertaccini, Assunta, Phyllis G. Weintraub, Govind Pratap Rao e Nicola Mori, eds. Phytoplasmas: Plant Pathogenic Bacteria - II. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-2832-9.

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Rao, Govind Pratap, Assunta Bertaccini, Nicola Fiore e Lia W. Liefting, eds. Phytoplasmas: Plant Pathogenic Bacteria - I. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-0119-3.

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Bertaccini, Assunta, Kenro Oshima, Michael Kube e Govind Pratap Rao, eds. Phytoplasmas: Plant Pathogenic Bacteria - III. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-9632-8.

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Maloy, Stanley R. Genetic analysis of pathogenic bacteria: A laboratory manual. Plainview, N.Y: Cold Spring Harbor Laboratory Press, 1996.

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Capítulos de livros sobre o assunto "Pathogenic bacteria"

Rodriguez, G. Marcela, e Issar Smith. "Pathogenic Mycobacteria". In Iron Transport in Bacteria, 360–71. Washington, DC, USA: ASM Press, 2014. http://dx.doi.org/10.1128/9781555816544.ch23.

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Boucias, Drion G., e Jacquelyn C. Pendland. "Insect Pathogenic Bacteria". In Principles of Insect Pathology, 177–216. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-4915-4_6.

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Peralta, E. G., e L. W. Ream. "T-DNA Border Sequences Required for Crown Gall Tumorigenesis". In Plant Pathogenic Bacteria, 1–10. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3555-6_1.

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Jen, G., e M. D. Chilton. "Structure and Properties of Border Sequences in T-DNA Transformation". In Plant Pathogenic Bacteria, 77–78. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3555-6_10.

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Perry, K. L., T. Simonitch, K. Harrison-Lavoie e S. T. Liu. "Cloning Regulation and Expression of Yellow Pigment Genes from Erwinia Herbicola". In Plant Pathogenic Bacteria, 477. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3555-6_100.

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Fuchs, R. L., S. A. McPherson e D. J. Drahos. "Cloning and Expression of a Serratia Marcescens Gene Encoding Chitinase". In Plant Pathogenic Bacteria, 478. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3555-6_101.

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Haas, J. M., W. F. Fett e D. J. Fleming. "Detection and Initial Characterization of Plasmids in Xanthomonas Campestris Pv. Glycines". In Plant Pathogenic Bacteria, 479. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3555-6_102.

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Mathews, D., J. Lukens e R. D. Durbin. "Current Status on Mode of Action Studies with Tagetitoxin". In Plant Pathogenic Bacteria, 481–83. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3555-6_103.

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Patil, Suresh S., D. E. Clements, C. J. Romeo e H. V. Kamdar. "Cloning of Genes Encoding Phaseolotoxin". In Plant Pathogenic Bacteria, 484–86. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3555-6_104.

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Peet, R. C., P. B. Lindgren e N. J. Panopoulos. "Molecular Genetics of Phaseolotoxin Production and Immunity in Pseudomonas Syringae Pv. Phaseolicola". In Plant Pathogenic Bacteria, 487–97. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3555-6_105.

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Trabalhos de conferências sobre o assunto "Pathogenic bacteria"

Broeseker, T. A., M. D. P. Boyle e R. Lottenberg. "PATHOGENIC BACTERIA HAVE HIGH AFFINITY RECEPTORS SPECIFIC FOR PLASMIN". In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644391.

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Binding of the key fibrinolytic enzyme, plasmin, to certain pathogenic group A streptococci was studied. In these experiments the ability of a group A streptococcal strain, 64/14, to bind either 125I-human plasminogen or the same label following activation with urokinase was measured. It was found that this strain bound <10% of the labeled plasminogen but >70% of labeled plasmin. This property distinguishes the plasmin receptor from streptokinase. These bacteria did not express a common serine protease receptor/inhibitor since they failed to bind labeled trypsin or urokinase. Maximal binding of plasmin occurred between pH 6.0 and 8.0 and in the ionic strength range of 50-200 mM salt. The Kd of plasmin binding to bacteria was approximately 10-10 M at pH 7.4 in 150 mM salt. This was determined by a non-linear least squares analysis of equilibrium binding data. Binding was reversibly inhibited by either epsilon aminocaproic acid (I50 of 0.2 mM) or lysine (I50 of 3.0 mM) suggesting the involvement of the high affinity lysine binding site of plasmin in its binding to bacteria. Bacterial bound plasmin retains its enzymatic activity, being capable of cleaving chromogenic substrates and solubilizing a fibrin- clot. The bacterial bound enzyme activity was inhibited by the low molecular weight inhibitors aprotinin and phe-pro-arg chloromethyl ketone but not by alpha-2 plasmin inhibitor. The ability of bacteria to acquire membrane associated proteolytic activity which cannot be physiologically inhibited may contribute to their tissue invasive properties.

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Galieva, Gulnaz, Kamalya Karamova, Polina Galitskaya e Svetlana Selivanovskaya. "PATHOGENIC POLLUTION OF CROPS CAUSING BY CHIKEN MANURE BASED FERTILIZERS". In 22nd SGEM International Multidisciplinary Scientific GeoConference 2022. STEF92 Technology, 2022. http://dx.doi.org/10.5593/sgem2022v/6.2/s25.33.

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Chicken manure is one of the most wide spread waste worldwide. One of its hazardous properties is contamination with live pathogens or pathogens� spores. Being introduced into soil for fertilization, fresh, cured or treated manure can cause soil contamination with those pathogens. Further, transmission of the pathogens through soil and plant tissues to human or animal food is possible. The objective of the present work was to reveal the level of pathogenic contamination of wheat grains cultivated on soil that was previously treated with cured chicken manure. Two types of manures M1 and M2 sampled from the large poultry farms situated in Russia were used to fertilize soil and obtain wheat grains (samples G1 and G2, respectively). Grains obtained with mineral fertilizers were used as a control (G0). Among 10 pathogenic bacterial species investigated, 6 were detected in both M1 and M2 samples - Listeria monocytogenes, Mycobacterium paratuberculosis,, Enterococus spp,, Campylobacter jejuni,, Bacillus anthracis,, Streptococcus dysgalactiae, the gene copy numbers for those bacteria revealed using RT-PCR was found to range between 2.22*104 and 1.19*108 gene copies per g manure. 5 of those species, except of C. jejuni, were also detected in both types of grains, while the gene copies number were found to be lower, thus they ranged between 1.45*103 and 8.81*103 copies per g grain. No bacterial pathogens were detected in G0 sample. Viral particles of bursal disease virus and avian orthoreovirus were not found either in manures nor in grains. It can be concluded that the risk of pathogenic transmission from the manures to grains exists, and that higher attention should be paid on their treatment to avoid the secondary infection of livestock and human.

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Munro, Hannah J. "Pathogenic bacteria inIxodes uriaein Newfoundland and Labrador". In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.107869.

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Mittal, Nikita, e Alok Bharadwaj. "Surveillance of Pathogenic Bacteria from Milk Samples". In 2021 5th International Conference on Information Systems and Computer Networks (ISCON). IEEE, 2021. http://dx.doi.org/10.1109/iscon52037.2021.9702341.

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Breitrück, Anne, Bernd Kreikemeyer e K. M. Henkel. "Antipathogenic Coatings for Antibiotics Reduction in Broiler Farming". In ITSC 2023. ASM International, 2023. http://dx.doi.org/10.31399/asm.cp.itsc2023p0717.

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Abstract In the current work, typical thermal-sprayed copper-based alloys are investigated to reduce the spread of pathogenic germs in broiler farming. Compressed air and nitrogen are used as process gas, while the coating torches and the alloys were varied. The results demonstrate a significant reduction in pathogenic load due to the coatings. This accounts especially for the bacterial strain E.ceocurm, which is the predominant bacteria in broiler farming. Further investigations regarded the microstructure and the electrical conductivity of the coatings.

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Sinha, Ashok, Ranjan Ganguly e Ishwar K. Puri. "Immunomagnetic Separation in Microchannels: From MEMS to BioNEMS". In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-81569.

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Conventional methods of monitoring and testing water quality involve collection of the sample to be tested and its subsequent analysis in a research laboratory for which some procedures may not be feasible or even accessible under certain field situations. Therefore, next generation sensors are required. Herein, an innovative concept that combines a micromixer and microparticle trap is proposed that should enable more rapid pathogen detection in contaminated water. In it, immunomagnetic separation (a procedure [1,2] that is well practiced in the field of immunochemistry) is scaled down from the benchtop to the microscale. Our design is generic, i.e., design is not limited to the detection of waterborne biological agents, but can be used for other forms of chemical analysis. Testing for waterborne bacteria requires analysis methods that must meet a number of challenging criteria. Time and sensitivity of analysis are the more important limitations. Bacterial detection methods have to be rapid and very sensitive since the presence of even a small pathogenic sample may sometimes constitute an infectious or otherwise harmful dose. Selective detection is also required because small numbers of pathogenic bacteria are often present in a complex biological environment along with many other nonpathogenic organisms. As an example, the infectious dosage of a pathogen such as E. coli O157:H7 or Salmonella is as low as 10 cells and the existing coliform standard for E. coli in water is 4 cells: 100 ml [3].

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Yakubovskaya, A. I., I. A. Kameneva, T. N. Melnichuk, T. V. Matveeva, M. V. Gritchin e S. F. Abdyrashitov. "Agrobacterium tumefaciens - associative microsymbionts of grain crop". In 2nd International Scientific Conference "Plants and Microbes: the Future of Biotechnology". PLAMIC2020 Organizing committee, 2020. http://dx.doi.org/10.28983/plamic2020.281.

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The installed absence of Ti-plasmids in the genome structure of strains of diazotrophic bacteria Agrobacterium tumefaciens 32 and A. tumefaciens P3 was found, which characterizes the strains as non-pathogenic. Bacterization of grain seeds by associative bacterial strains stimulates root development by up to 40%.

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Rahmayuna, Novita, Dewangga Satriya Rahardwika, Christy Atika Sari, De Rosal Ignatius Moses Setiadi e Eko Hari Rachmawanto. "Pathogenic Bacteria Genus Classification using Support Vector Machine". In 2018 International Seminar on Research of Information Technology and Intelligent Systems (ISRITI). IEEE, 2018. http://dx.doi.org/10.1109/isriti.2018.8864478.

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Boyle, Michael, Tim Ford, Ralph Mitchell e James Maki. "Survival of Pathogenic Bacteria Under Nutrient Starvation Conditions". In International Conference On Environmental Systems. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 1990. http://dx.doi.org/10.4271/901381.

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Al-Otaibi, D. S., A. A. Akbar, H. Drobiova, C. Obuekwe e E. Al-Saleh. "Dissemination of potentially pathogenic bacteria into the environment". In ENVIRONMENTAL HEALTH RISK 2009. Southampton, UK: WIT Press, 2009. http://dx.doi.org/10.2495/ehr090151.

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Relatórios de organizações sobre o assunto "Pathogenic bacteria"

Walsh, Marie K., Daryll B. De Wald e Bart C. Weimer. Biomimetic Sensor for Pathogenic Bacteria. Fort Belvoir, VA: Defense Technical Information Center, março de 2001. http://dx.doi.org/10.21236/ada387395.

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Wu, Chi-Fang, James J. Valdes, Jennifer W. Sekowski e William E. Bentley. Identification of Multiple Pathogenic Bacteria Using a DNA Microarray. Fort Belvoir, VA: Defense Technical Information Center, outubro de 2002. http://dx.doi.org/10.21236/ada408810.

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Fischetti, Vincent A. Using Phage Lytic Enzymes to Destroy Pathogenic and BW Bacteria. Fort Belvoir, VA: Defense Technical Information Center, julho de 2005. http://dx.doi.org/10.21236/ada436735.

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Rahman, Salma. Exploration of Simple Analytical Approaches for Rapid Detection of Pathogenic Bacteria. Office of Scientific and Technical Information (OSTI), janeiro de 2005. http://dx.doi.org/10.2172/861631.

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Prevost, Pierce, e Dawn Simms. Fomites in the Fitness Center: Fitness Equipment Harbors Antibiotic Resistant and Pathogenic Bacteria. Journal of Young Investigators, fevereiro de 2021. http://dx.doi.org/10.22186/jyi.39.2.16-21.

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Cytryn, Eddie, Mark R. Liles e Omer Frenkel. Mining multidrug-resistant desert soil bacteria for biocontrol activity and biologically-active compounds. United States Department of Agriculture, janeiro de 2014. http://dx.doi.org/10.32747/2014.7598174.bard.

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Control of agro-associated pathogens is becoming increasingly difficult due to increased resistance and mounting restrictions on chemical pesticides and antibiotics. Likewise, in veterinary and human environments, there is increasing resistance of pathogens to currently available antibiotics requiring discovery of novel antibiotic compounds. These drawbacks necessitate discovery and application of microorganisms that can be used as biocontrol agents (BCAs) and the isolation of novel biologically-active compounds. This highly-synergistic one year project implemented an innovative pipeline aimed at detecting BCAs and associated biologically-active compounds, which included: (A) isolation of multidrug-resistant desert soil bacteria and root-associated bacteria from medicinal plants; (B) invitro screening of bacterial isolates against known plant, animal and human pathogens; (C) nextgeneration sequencing of isolates that displayed antagonistic activity against at least one of the model pathogens and (D) in-planta screening of promising BCAs in a model bean-Sclerotiumrolfsii system. The BCA genome data were examined for presence of: i) secondary metabolite encoding genes potentially linked to the anti-pathogenic activity of the isolates; and ii) rhizosphere competence-associated genes, associated with the capacity of microorganisms to successfully inhabit plant roots, and a prerequisite for the success of a soil amended BCA. Altogether, 56 phylogenetically-diverse isolates with bioactivity against bacterial, oomycete and fungal plant pathogens were identified. These strains were sent to Auburn University where bioassays against a panel of animal and human pathogens (including multi-drug resistant pathogenic strains such as A. baumannii 3806) were conducted. Nineteen isolates that showed substantial antagonistic activity against at least one of the screened pathogens were sequenced, assembled and subjected to bioinformatics analyses aimed at identifying secondary metabolite-encoding and rhizosphere competence-associated genes. The genome size of the bacteria ranged from 3.77 to 9.85 Mbp. All of the genomes were characterized by a plethora of secondary metabolite encoding genes including non-ribosomal peptide synthase, polyketidesynthases, lantipeptides, bacteriocins, terpenes and siderophores. While some of these genes were highly similar to documented genes, many were unique and therefore may encode for novel antagonistic compounds. Comparative genomic analysis of root-associated isolates with similar strains not isolated from root environments revealed genes encoding for several rhizospherecompetence- associated traits including urea utilization, chitin degradation, plant cell polymerdegradation, biofilm formation, mechanisms for iron, phosphorus and sulfur acquisition and antibiotic resistance. Our labs are currently writing a continuation of this feasibility study that proposes a unique pipeline for the detection of BCAs and biopesticides that can be used against phytopathogens. It will combine i) metabolomic screening of strains from our collection that contain unique secondary metabolite-encoding genes, in order to isolate novel antimicrobial compounds; ii) model plant-based experiments to assess the antagonistic capacities of selected BCAs toward selected phytopathogens; and iii) an innovative next-generation-sequencing based method to monitor the relative abundance and distribution of selected BCAs in field experiments in order to assess their persistence in natural agro-environments. We believe that this integrated approach will enable development of novel strains and compounds that can be used in large-scale operations.

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Kapulnik, Yoram, e Donald A. Phillips. Isoflavonoid Regulation of Root Bacteria. United States Department of Agriculture, janeiro de 1996. http://dx.doi.org/10.32747/1996.7570561.bard.

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The overall objective of this project was to develop a conceptual framework for enhancing root colonization by beneficial bacteria. To accomplish this aim we tested the hypothesis that production and excretion of the plant phytoalexin medicarpin can be used for creation of a special niche along the legume roots, where beneficial microorganism, such as rhizobium, will have a selective advantage. On the Israeli side it was shown that higher medicarpin levels are exuded following the application of Rhizobium meliloti to the rhizosphere but the specific biochemical pathway governing medicarpin production was not induced significantly enough to support a constant production and excretion of this molecule to the rhizosphere. Furthermore, pathogenic bacteria and chemical elicitors were found to induce higher levels of this phytoalexin and it became important to test its natural abundance in field grown plants. On the US side, the occurrence of flavonoids and nucleosides in agricultural soils has been evaluated and biologically significant quantities of these molecules were identified. A more virulent Agrobacterium tumefaciens strain was isolated from alfalfa (Medicago sativa L.) which forms tumors on a wide range of plant species. This isolate contains genes that increase competitive colonization abilities on roots by reducing the accumulation of alfalfa isoflavonoids in the bacterial cells. Following gene tagging efforts the US lab found that mutation in the bacterial efflux pump operons of this isolate reduced its competitive abilities. This results support our original hypothesis that detoxification activity of isoflavenoids molecules, based on bacterial gene(s), is an important selection mechanism in the rhizosphere. In addition, we focused on biotin as a regulatory element in the rhizosphere to support growth of some rhizosphere microorganisms and designed a bacterial gene construct carrying the biotin-binding protein, streptavidin. Expressing this gene in tobacco roots did not affect the biotin level but its expression in alfalfa was lethal. In conclusion, the collaborative combination of basic and applied approaches toward the understanding of rhizosphere activity yielded new knowledge related to the colonization of roots by beneficial microorganisms in the presence of biological active molecules exuded from the plant roots.

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Kalchayanand, Norasak, Bibek Ray, Anthony Sikes e C. P. Dunne. Destruction of Spoilage and Pathogenic Bacteria by Hydrostatic Pressure and Electroporation in Combination with Biopreservatives. Phase 2. Fort Belvoir, VA: Defense Technical Information Center, abril de 1997. http://dx.doi.org/10.21236/ada324258.

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Yedidia, I., H. Senderowitz e A. O. Charkowski. Small molecule cocktails designed to impair virulence targets in soft rot Erwinias. Israel: United States-Israel Binational Agricultural Research and Development Fund, 2020. http://dx.doi.org/10.32747/2020.8134165.bard.

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Chemical signaling between beneficial or pathogenic bacteria and plants is a central factor in determining the outcome of plant-microbe interactions. Pectobacterium and Dickeya (soft rot Erwinias) are the major cause of soft rot, stem rot, and blackleg formed on potato and ornamentals, currently with no effective control. Our major aim was to establish and study specific bacterial genes/proteins as targets for anti-virulence compounds, by combining drug design tools and bioinformatics with experimental work. The approach allowed us to identify and test compounds (small molecules) that specifically interfere with the activities of these targets, by this impairing bacterial virulence. Two main targets were selected within the frame of the BARD project. The first is the ATP-binding cassette (ABC) transporters and methyl-accepting chemotaxis proteins (MCP) that have been characterized here for the first time in Pectobacteriaceae, and the second is the quorum sensing (QS) machinery of Pectobacterium with its major proteins and in particular, the AHL synthase ExpI that was identified as the preferred target for inhibition. Both systems are strongly associated with bacterial virulence and survival in planta. We found that Pectobacteriaceae, namely Dickeya and Pectobacterium, encode more ABC transporters and MCP in their genomes, compared to other bacteria in the order. For MCP, soft rot Pectobacteriaceae not only contain more than 30 MCP genes per strain, but also have more diverse ligand binding domains than other species in the Enterobacteriales. These findings suggest that both ABC transporters and MCP are important for soft rot Pectobacteriaceae pathogenicity. We now have a selection of mutants in these proteins that may be further explored to understand their direct involvement in virulence. In parallel, we studied the QS central proteins in pectobacteria, the signaling molecule N-acyl-homoserine lactone synthase, ExpI, and the response regulator ExpR, and established their phylogenetic relations within plant pathogenic Gram negative bacteria. Next, these proteins were used for virtual screening of millions of compounds in order to discover new compounds with potential to interfere with the QS machinery. Several natural compounds were tested for their interference with virulence related traits in Pectobacterium and their capability to minimize soft rot infections. Our findings using microcalorimetric binding studies have established for the first time direct interaction between the protein ExpI and two natural ligands, the plant hormone salicylic acid and the volatile compound carvacrol. These results supported a model by which plants interfere with bacterial communication through interkingdom signaling. The collaborative project yielded two research papers and a comprehensive review, which included new computational and bioinformatics data, in Annu. Rev. Phytopathol., the highest ranked journal in phytopathology. Additional two papers are in preparation. In order to transform the fundamental knowledge that have been gained during this collaborative BARD project into agricultural practice, to control soft rot bacteria, we have submitted a continual project.

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Coplin, David L., Shulamit Manulis e Isaac Barash. roles Hrp-dependent effector proteins and hrp gene regulation as determinants of virulence and host-specificity in Erwinia stewartii and E. herbicola pvs. gypsophilae and betae. United States Department of Agriculture, junho de 2005. http://dx.doi.org/10.32747/2005.7587216.bard.

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Gram-negative plant pathogenic bacteria employ specialized type-III secretion systems (TTSS) to deliver an arsenal of pathogenicity proteins directly into host cells. These secretion systems are encoded by hrp genes (for hypersensitive response and pathogenicity) and the effector proteins by so-called dsp or avr genes. The functions of effectors are to enable bacterial multiplication by damaging host cells and/or by blocking host defenses. We characterized essential hrp gene clusters in the Stewart's Wilt of maize pathogen, Pantoea stewartii subsp. stewartii (Pnss; formerly Erwinia stewartii) and the gall-forming bacterium, Pantoea agglomerans (formerly Erwinia herbicola) pvs. gypsophilae (Pag) and betae (Pab). We proposed that the virulence and host specificity of these pathogens is a function of a) the perception of specific host signals resulting in bacterial hrp gene expression and b) the action of specialized signal proteins (i.e. Hrp effectors) delivered into the plant cell. The specific objectives of the proposal were: 1) How is the expression of the hrp and effector genes regulated in response to host cell contact and the apoplastic environment? 2) What additional effector proteins are involved in pathogenicity? 3) Do the presently known Pantoea effector proteins enter host cells? 4) What host proteins interact with these effectors? We characterized the components of the hrp regulatory cascade (HrpXY ->7 HrpS ->7 HrpL ->7 hrp promoters), showed that they are conserved in both Pnss and Fag, and discovered that the regulation of the hrpS promoter (hrpSp) may be a key point in integrating apoplastic signals. We also analyzed the promoters recognized by HrpL and demonstrated the relationship between their composition and efficiency. Moreover, we showed that promoter strength can influence disease expression. In Pnss, we found that the HrpXY two-component signal system may sense the metabolic status of the bacterium and is required for full hrp gene expression in planta. In both species, acyl-homoserine lactone-mediated quorum sensing may also regulate epiphytic fitness and/or pathogenicity. A common Hrp effector protein, DspE/WtsE, is conserved and required for virulence of both species. When introduced into corn cells, Pnss WtsE protein caused water-soaked lesions. In other plants, it either caused cell death or acted as an Avr determinant. Using a yeast- two-hybrid system, WtsE was shown to interact with a number of maize signal transduction proteins that are likely to have roles in either programmed cell death or disease resistance. In Pag and Pab, we have characterized the effector proteins HsvG, HsvB and PthG. HsvG and HsvB are homologous proteins that determine host specificity of Pag and Pab on gypsophila and beet, respectively. Both possess a transcriptional activation domain that functions in yeast. PthG was found to act as an Avr determinant on multiple beet species, but was required for virulence on gypsophila. In addition, we demonstrated that PthG acts within the host cell. Additional effector genes have been characterized on the pathogenicity plasmid, pPATHₚₐg, in Pag. A screen for HrpL- regulated genes in Pnsspointed up 18 candidate effector proteins and four of these were required for full virulence. It is now well established that the virulence of Gram-negative plant pathogenic bacteria is governed by Hrp-dependent effector proteins. However; the mode of action of many effectors is still unresolved. This BARD supported research will significantly contribute to the understanding of how Hrp effectors operate in Pantoea spp. and how they control host specificity and affect symptom production. This may lead to novel approaches for genetically engineering plants resistant to a wide range of bacterial pathogens by inactivating the Hrp effectors with "plantabodies" or modifying their receptors, thereby blocking the induction of the susceptible response. Alternatively, innovative technologies could be used to interfere with the Hrp regulatory cascade by blocking a critical step or mimicking plant or quorum sensing signals.

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