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1
Steward, Karen Frances. "Comparative genomics of Streptococcus equi and Streptococcus zooepidemicus." Thesis, University of Cambridge, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708551.
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Maciel, Liana Flores. "Desenvolvimento de vacina recombinante de proteína M de Streptococcus equi subsp. equi." Universidade Federal de Pelotas, 2012. http://repositorio.ufpel.edu.br/handle/ri/1199.
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Previous issue date: 2012-02-28The business related to equines in Brazil has an important participation in activities as leisure, culture and tourism, being responsible for millions of jobs. The equine distemper caused by Streptococcus equi subsp. equi is a disease of the respiratory tract with economical impact, generating losses with treatment and reduction in the animal performance. To solve this problem, prophylactic measures, such as the vaccination, are important. However, available commercial vaccines do not offer protection to more than 50% of the vaccinated animals. Several studies are being performed aiming the achievement of an efficient vaccine against the Adenitis, where several virulence factors are being evaluated as possible vaccine antigens, specially the M protein (SeM). Thus, the present work aimed the development and evaluation of a recombinant vaccine to the control of the equine distemper composed of the SeM antigen co-administrated with the recombinant Heat-labile enterotoxin B subunit of Escherichia coli (rLTB) and/or aluminium hydroxide (Al(OH)3). A total of 72 female BALB/c mice, divided into eight groups and 18 horses, divided into six groups, were inoculated by intramuscular or intranasal routes. The results obtained in the experiments showed that the rSeM was innocuous and immunogenic in both evaluated species, stimulating the production of specific immunoglobulin anti-rSeM without the addition of immunological adjuvant. Both adjuvant rLTB and Al(OH)3 were not capable to increase the titer of immunoglobulin anti-rSeM in mice, while in horses, the treatment rSeM + rLTB (IM) showed a significant increase in the level of seric immunoglobulin IgG anti-rSeM. Interestingly, the production of anti-rSeM secretory IgA in the upper respiratory tract has a significant increase in horses treated with rSeM + Al(OH)3 (IM). This result is promising to further studies with rSeM as an antigen for vaccines, as well as is the administration of rLTB as an immunological adjuvant.
A equinocultura no Brasil ganha espaço em setores ligados ao lazer, cultura e turismo, sendo responsável por milhões de empregos. A Adenite Equina causada pelo Streptococcus equi subsp. equi é uma doença do aparelho respiratório de elevado impacto econômico, gerando gastos com mão-de-obra e perda de desempenho dos animais. Para amenizar este problema, medidas profiláticas são importantes, como por exemplo, a vacinação. Porém, as vacinas disponíveis no mercado protegem apenas 50% dos animais. Vários estudos vêm sendo realizados para obtenção de uma vacina mais eficiente contra a Adenite, onde vários fatores de virulência do patógeno estão sendo avaliados como possíveis antígenos vacinais, com destaque para a proteína M de S. equi (SeM). Com base nisso este trabalho objetivou o desenvolvimento e avaliação de uma vacina recombinante para controle da Adenite Equina, utilizando como antígeno a rSeM e como adjuvantes a subunidade B da enterotoxina termolábil de Escherichia coli (rLTB) e ou hidróxido de alumínio (Al(OH)3). Para este estudo foram utilizados 72 camundongos Balb/c fêmeas divididos em 8 grupos e 18 cavalos divididos em 6 grupos, inoculados por via IM ou IN. Os resultados mostraram que a rSeM foi inócua e imunogênica para ambas as espécies avaliadas, estimulando níveis significativos de imunoglobulinas (lgs) anti-rSeM sem a necessidade de uso de qualquer adjuvante imunológico. Os adjuvantes rLTB e Al(OH)3 não foram capazes de incrementar significativamente os títulos de lgs antirSeM em camundongos, enquanto que em cavalos o tratamento rSeM + rLTB (IM) promoveu um aumento significativo no título sérico de IgG anti-rSeM. Interessantemente, a produção de IgA secretória anti-rSeM no trato respiratório superior de cavalos teve aumento significativo no tratamento com rSeM + Al(OH)3 (IM). Estes resultados são promissores para a continuidade de estudos visando a utilização da rSeM como antígeno vacinal. Da mesma forma, o uso da rLTB como adjuvante em vacinas para cavalos parece ser promissor.
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De, Negri Rafaela. "EQUINE SERUM ANTIBODY RESPONSES TO STREPTOCOCCUS EQUI AND STREPTOCOCCUS ZOOEPIDEMICUS." UKnowledge, 2013. http://uknowledge.uky.edu/gluck_etds/13.
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Streptococcus zooepidemicus (Sz) and Streptococcus equi (Se) share 98% DNA sequence homology, but display different pathogenic properties. Infection by one organism does not cross-protect against the other. To better understand pathogenic differences between these organisms and gain information about which proteins are expressed in horses infected experimentally with Se, intrauterine Sz or naturally with respiratory Sz we compared antibody specificities of convalescent sera using ELISA. These comparisons were based on sets of 8 and 14 immunoreactive recombinant proteins of Se strain CF32 and Sz strain NC78, respectively. Sera from donkeys that were previously naturally affected with strangles and later developed Sz pneumonia secondary to an experimental influenza challenge were also included.
Serum antibody responses were quantitatively and qualitatively much greater following recovery from strangles than following respiratory Sz infection. Increased reactions to Se proteins IdeE2, Se75.3, Se46.8, Se18.9 and Se42.0 were observed for the majority of strangles sera but not for sera from respiratory Sz infection cases. Reactions of sera from Sz respiratory disease to Sz proteins varied greatly and were mostly to HylC and ScpC. Interestingly, sera of donkey recovered from Sz bronchopneumonia did not show increased antibody reaction to any of the proteins even though these donkeys had also recovered from clinical strangles 6 months previously. Only 1/5 mare with Sz placentitis presented increased serum antibody responses to MAP. In conclusion, adaptive immune responses to Se of horses with strangles are stronger and involve a greater number of proteins than adaptive immune responses to Sz infection of the lower respiratory tract.
In an effort to develop an improved vaccine against Se, modified live strain of EHV-1, RacH was constructed to express three recombinant antigens of Se SeM, IdeE and Se18.9. Two groups of 10 and 2 ponies were vaccinated intramuscularly or intranasally, respectively. Another group (n=6) vaccinated with empty RacH served as controls. Sera from 2/3 ponies from each vaccination groups and 1/2 serum from IN vaccinated ponies showed increased serum neutralizing antibodies to EHV-1. ELISA detected no significant increase in antibodies to proteins. Only one IM and IN vaccinated pony showed serum bactericidal activity post vaccination.
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Lannergård, Jonas. "Potentially virulence-related extracellular proteins of Streptococcus equi /." Uppsala : Dept. of Microbiology, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/200680.pdf.
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Silva, Marta Uva Cansado Gonçalves. "Clínica e cirurgia de equinos." Master's thesis, Universidade de Évora, 2019. http://hdl.handle.net/10174/25901.
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Este relatório tem como objetivo a descrição das atividades desenvolvidas durante o estágio curricular do Mestrado Integrado em Medicina Veterinária da Universidade de Évora.
A primeira parte consiste numa apresentação da casuística acompanhada, dividida pelas áreas da medicina preventiva, clínica e cirúrgica de equinos, bem como a área da reprodução, descrevendo-se alguns procedimentos ou casos clínicos mais relevantes.
A segunda parte consiste numa monografia sobre o tema “Gurma: infeção do trato respiratório superior de equinos por Streptococcus equi subsp. equi”, com foco na deteção e tratamento de portadores crónicos assintomáticos por endoscopia.
Por último, desenvolvem-se alguns casos decorrentes de um surto de gurma acompanhado durante o estágio, na região do Alentejo; Abstract:
Equine Clinics and Surgery
This report is meant to account for the activities developed throughout the internship integrated in the master’s degree in Veterinary Medicine of the University of Évora.
The first section consists in a description of the case load performed in the different areas of the equine prophylaxis, clinics and surgery, as well as breeding. When relevant, some procedures or cases are more minutely described.
In the second section a monograph on “Strangles: an equine upper respiratory tract infection by Streptococcus equi subsp. equi” is made, focusing on the endoscopic detection and treatment of chronic asymptomatic carriers.
Lastly, some relevant cases of a strangles outbreak that occurred during the internship period, in the Alentejo region, are reported.
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Karlström, Åsa. "Collagen-like proteins in horse pathogenic Streptococcus equi /." Uppsala : Dept. of Microbiology, Swedish University of Agricultural Sciences, 2005. http://epsilon.slu.se/200599.pdf.
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Lindmark, Hans. "Characterization of adhesive extracellular proteins from Streptococcus equi /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5488-3.pdf.
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Libardoni, Felipe. "Equinos portadores de Streptococcus equi subespécie equi: prevalência, fatores de risco e caracterização de alelos seM." Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/4105.
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Strangles is considered the main respiratory disease in horses. The etiologic agent is the bacterium Streptococcus equi subsp. equi (S. equi), responsible for approximately 30% of horse diseases worldwide notifications. The clinical signs of strangles are fever, nasal secretion and lymph node enlargement. The last one occurs due the incomplete phagocytosis of S. equi by defense cells because bacterial hyaluronic acid capsule and M protein (SeM). The epidemiology, the risk factors and the strangles control are poorly understood. The 5' end of the seM gene sequence has been used for isolate differentiation by characterization of the alleles. Therefore, this thesis aimed to study the prevalence of Streptococcus equi subsp. equi (S. equi) in healthy horses, the alleles frequency and the risk factors involved on equine adenitis. One thousand and ten nasal swabs were obtained from healthy horses from 341 farms. Twenty four horses were positive for S. equi, confirmed by PCR and DNA sequencing. The prevalence of S. equi per equine was 2.37%, and 20 farms were positive (5.86%). Risk factor analysis showed by confirming and quantifying statistically that: the number of agglomeration events that horses participate (RR: 1.6), the situation with food container shared (RR: 3.74) and the positive diagnosis for adenitis (RR: 3.20) are significant risk factors for Strangles. These results provide important epidemiological contribution to the equine industry and can give support for the disease control. In addition, the 5 'end of the gene seM was amplified by PCR and sequenced and allele characterized. It was found the same allele (SEM-61) in all the samples. These results support the hypothesis of natural selection of alleles apparently more suited to survive, persist and perpetuate in the population studied.A adenite equina é uma doença infecto-contagiosa que acomete o trato respiratório superior, sendo uma das principais doenças respiratórias de equinos. O agente etiológico dessa enfermidade é o Streptococcus equi subespécie equi (S. equi), responsável por aproximadamente 30% das notificações em todo o mundo. Os principais sinais clínicos da adenite são febre, secreção nasal e enfartamento de linfonodos, que ocorre pela dificuldade de fagocitose do S. equi por células de defesa devido a presença da cápsula de ácido hialurônico e proteína M. O entendimento sobre a epidemiologia, a análise de fatores de risco para adenite equina e o controle dessa enfermidade ainda são limitados. Estudos moleculares demonstram diferenças na extremidade 5 da sequência do gene (seM) codificador da proteína M de S. equi. Esta região do gene já foi utilizada na diferenciação de isolados por meio da caracterização de diferentes alelos. Por tudo isso, essa tese objetivou obter resultados de prevalência, e também análise de fatores de risco para adenite equina através de um desenho experimental para coleta de suabes nasais. Foram obtidos 1.010 suabes nasais de equinos sadios em 341 fazendas, de onde foram identificados 24 equinos positivos para S. equi em isolamento, que posteriormente foram confirmados por PCR e sequenciamento de DNA. A prevalência estimada por equino foi de 2.37%, e 20 fazendas foram consideradas positivas (5.86%). Na análise de fatores de risco, foi comprovado e quantificado estatisticamente que: número de eventos de aglomeração que os equinos participam (RR:1.06), o ato de compartilhar recipiente de alimento (RR:3.74) e ter tido diagnóstico positivo para adenite (RR:3.20) são fatores de risco relevantes para adenite equina. Estes resultados oferecem contribuições epidemiológicas importantes para a indústria de equinos e pode apoiar o controle da doença. Em paralelo, a região 5 terminal do gene seM das 24 amostras positivas foi amplificada por PCR e sequenciada para caracterização de alelos, sendo identificado o mesmo alelo (seM-61) em todas as amostras. Esses resultados evidenciam a hipótese de seleção natural de alelos aparentemente mais adaptados a sobreviver, persistir e se perpetuar na população estudada.
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West, Douglas Anthony. "In vitro analysis of the role of the Streptococcus equi subspecies equi hyaluronic acid capsule in virulence." Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.616143.
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Freislerová, Eva. "Produkce kyseliny hyaluronové covRS-deficientním kmenem Streptococcus equi subsp. zooepidemicus." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2018. http://www.nusl.cz/ntk/nusl-240561.
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The bacteria of genus Streptococci are among the most significant producers of hyaluronic acid in industrial scale. One of the typical representatives of that group is Streptococcus equi subsp. zooepidemicus. The production of hyaluronic acid in Streptococcus equi subsp. zooepidemicus is heavily influenced by cultivation conditions and by genetic alterations. The present work describes the deletion of genes covR and covS responsible for transcriptional regulation of stress response. According to Galeas a kol. [35] the deletion of these genes in S. pyogenes led to the hyaluronic acid capsule increase. As the S. pyogenes and S. equi subsp. zooepidemicus share approx. 80 % of genome, it was assumed, that the deletion of genes covR and covS in Streptococcus equi subsp. zooepidemicus genome would lead to the higher hyaluronic acid production. The new strain SEZ covRS was obtained by allelic replacement mutagenesis. The cultivations performed in laboratory-scale fermenters in rich Wheat E1 medium showed approx. 9% higher production over parental strain. Therefore, the covRS regulation system plays the same role in Streptococcus equi subsp. zooepidemicus and indirectly regulates the biosynthesis of hyaluronic acid.
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Libardoni, Felipe. "Epidemiologia molecular de surtos de Adenite equina no Rio Grande do Sul Brasil." Universidade Federal de Santa Maria, 2012. http://repositorio.ufsm.br/handle/1/10128.
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Strangles is an equine infectious disease that affects the upper respiratory tract, being
considered the main respiratory disease in horses. The etiologic agent is Streptococcus equi
subsp. equi (S. equi), responsible for approximately 30% of horse diseases worldwide
notifications. The clinical signs of strangles are fever, nasal secretion and lymph node
enlargement. The last one occurs due the incomplete phagocytosis of S. equi by defense cells
because the presence of hyaluronic acid capsule and M protein (SeM) on the bacteria. The
understanding of strangles epidemiology and its control is still limited. Molecular studies
demonstrate differences in the gene sequence that codify the N-terminal region of the M
protein (SeM) of S. equi. This gene region was already used in the differentiation of isolates
by characterization of different alleles. This thesis aims to analyze and differentiate 47 S. equi
isolates from equine clinical specimens from southern Brazil (15 Thoroughbred horses, 29
animals from the Crioula breed and three Brasileiro de Hipismo) through phylogenetic
analysis and differentiation of alleles based on sequencing of the N-terminal region of the
SeM protein. Samples were obtained from 31 outbreaks in 20 premises. Fifteen alleles were
identified being only one (allele 9), with 7 isolates (14.9%), was already available in the
PubMLST-SeM database (allele 61). Among the new identified alleles, the number 1 was the
most prevalent with 13 isolates (27.7%), followed by allele 3 with 10 isolates (21.3%). The
results demonstrate the great diversity of the amino acid sequence among the S. equi isolates
from the studied equine population. Therefore the N-terminal sequence of SeM gene of the S.
equi isolates is a useful tool in epidemiological investigation to differentiate isolates in
strangles outbreaks with the identification of alleles in horses population, and may represent
an alternative for to control the illness with guidance in selecting strains for production of
commercial and autogenous vaccines.A adenite equina é uma doença infecto-contagiosa que acomete o trato respiratório superior, sendo uma das principais doenças respiratórias de equinos. O agente etiológico dessa enfermidade é o Streptococcus equi subespécie equi (S. equi), responsável por aproximadamente 30% das notificações em todo o mundo. Os principais sinais clínicos da adenite são febre, secreção nasal e enfartamento de linfonodos, que ocorre pela dificuldade de fagocitose do S. equi por células de defesa devido a presença da cápsula de ácido hialurônico e proteína M. Somado a isso, o entendimento sobre a epidemiologia e o controle da adenite equina ainda é limitado. Estudos moleculares demonstram diferenças na região N-terminal na sequência do gene codificador da proteína M (SeM) de S. equi. Esta região do gene já foi utilizada na diferenciação de isolados por meio da caracterização de diferentes alelos. Esta dissertação objetivou analisar e diferenciar 47 isolados bacterianos de S. equi provenientes de amostras clínicas de equinos da região sul do Brasil, oriundas de 15 animais Puro Sangue de Corrida (PSC), 29 da raça Crioula e três da raça Brasileiro de Hipismo (BH), por meio de análise filogenética e diferenciação de alelos, com base no sequenciamento da região Nterminal do gene SeM. As amostras foram oriundas de 31 surtos em 20 estabelecimentos de criação. Foram encontrados 15 alelos de SeM, dentre os quais apenas um (alelo 9) já disponível no banco de dados PubMLST-SeM, como alelo 61, com sete isolados (14,9%). Entre os novos alelos identificados, o alelo 1 foi o mais prevalente com 13 isolados (27,7%), seguido pelo alelo 3 com 10 isolados (21,3%). Os resultados demonstram a grande diversidade da proteína M entre os isolados de S. equi na população equina estudada. Portanto, o sequenciamento parcial do gene da proteína M do S. equi é uma ferramenta útil na investigação epidemiológica para a diferenciação de isolados em surtos de adenite equina, com a identificação de alelos em populações de equinos. Além disso, pode representar uma perspectiva para o controle da enfermidade com a orientação na escolha de cepas para confecção de vacinas comerciais e autógenas.
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Becerra, Martínez José Luis Elías. "Obtención de una proteína recombinante PsaA de Streptococcus pneumoniae, homóloga a una de Streptococcus equi." Tesis, Universidad de Chile, 2005. http://repositorio.uchile.cl/handle/2250/130773.
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Memoria para optar al Título Profesional de Médico VeterinarioLos streptococos patógenos para los equinos incluyen S. equi subsp. equi (S. equi), S. equi subsp. zooepidemicus, S. dysgalactiae subsp. equisimilis y S. pneumoniae cápsula Tipo III. S. equi causa gurma, una linfoadenitis purulenta altamente contagiosa que afecta a los miembros de la familia Equidae. Rápidos progresos se han realizado para la identificación de factores de virulencia y proteínas de S. equi. La mayoría de éstas son expresadas en la superficie bacteriana o son secretadas. Se ha demostrado la presencia de una proteína homóloga a la pneumococcal surface adhesin A (PsaA) de S. pneumoniae, en S. zooepidemicus y S. equi. La PsaA de S. pneumoniae, como otras proteínas, es inmunogénica y protege animales de laboratorio ante un desafío con neumococos. El objetivo de esta memoria fue obtener desde un aislado clínico de S. pneumoniae, una PsaA recombinante purificada desde E. coli BL21DE3. La metodología consistió en amplificar el gen PsaA por PCR y ligarlo al plasmidio de clonamiento (pETBlue-1), luego con la mezcla de ligación PsaA/pSTBlue-1 se transformó la cepa E. coli DH5; de las colonias transformadas, se purificó el plasmidio (PsaA/pSTBlue-1) por lisis alcalina, el cual fue sometido a digestión doble y, el fragmento liberado, fue ligado finalmente a un vector de expresión (pET-15b). Con la mezcla de ligación PsaA/pET-15b, se transformó la cepa E. coli BL21DE3, que expresó una proteína fusionada a una cola de histidina; la proteína fusionada, a su vez, se purificó en una columna con afinidad por histidina (Ni-Nta). La presencia de rPsaA fue analizada mediante electroforesis en gel de poliacrilamida y por Western blot, observándose la presencia de una proteína de 37 kDa., con la que reaccionó específicamente el anticuerpo policlonal de conejo anti His-tag. La secuencia nucleotídica del fragmento fue comparada en la base de datos BLAST (www.ncbi.nlm.nih.gov), encontrándose un 98% de identidad con la cepa S. pneumoniae R6. Además se identificaron cuatro regiones, con identidades superiores al 80%, similares a las del gen parcial mba de la proteína ligadora de metal/adhesina de S. equi, homóloga a PsaA de S. pneumoniae. El producto obtenido permitirá realizar estudios de formulación y evaluación, en modelo animal, de un prototipo de vacuna contra el gurma, basado en la proteína PsaA de S. pneumoniae.
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Heather, Zoe. "Comparative and functional genomic analysis of Streptococcus equi and Streptococcus zooepidemicus : identifying novel vaccine targets." Thesis, Open University, 2009. http://oro.open.ac.uk/54823/.
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Streptococcus equi subspecies equi (S. equi) is a host-restricted pathogen of horses and the aetiological agent of strangles. Available evidence suggests that S. equi evolved from Streptococcus equi subspecies zooepidemicus (S. zooepidemicus), a versatile bacterium that is often isolated from the equine respiratory tract, but can cause opportunistic disease in horses and other animals. A comparison of the genomes of S. equi 4047 and S. zooepidemicus H70 and the screening of diverse S. equi and S. zooepidemicus strains uncovered the genetic events that have shaped the evolution of S. equi, and led to its emergence as a niche-adapted pathogen. This analysis provides evidence of functional loss, changes in the organisation and sequence of genes, and pathogenic specialisation through the acquisition of prophage encoding a phospholipase A2 toxin, and 4 superantigens, and an integrative conjugative element carrying a novel siderophore-like nonribosomal peptide synthetase (NRPS) system. The NRPS shares similarity with the yersiniabactin system found in the high pathogenicity island of Yersinia pestis and is the first of its kind to be identified in streptococci. As this genetic feature is absent from the S. zooepidemicus population, its gain is considered to have been a key event in the emergence of S. equi. Further work determined a role for the NRPS in iron acquisition, and through its heterologous reconstitution in Escherichia coli and/or the analysis of allelic replacement mutants in S. equi, identified biosynthetic genes, transporters involved in efflux and import of the NRPS product(s), salicylate as a substrate for the NRPS and its regulation by a novel iron-dependent IdeR-like repressor, using various in vitro growth assays, including sensitivity to streptonigrin and 55Fe accumulation. Possible vaccine targets were identified in both subspecies and existing diagnostic tools were improved, which included the development of a quantitative PCR test for the detection of S. equi.
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Delph, Katherine. "Comparison of immunologic responses following intranasal and oral administration of a USDA-approved, live-attenuated Streptococcus equi vaccine." Thesis, Kansas State University, 2016. http://hdl.handle.net/2097/32595.
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Master of ScienceDepartment of Clinical Science
Elizabeth Davis
Background: While there is a commercially-available vaccine for Streptococcus equi subsp. equi licensed for the intranasal route of administration, some equine practitioners are administering this vaccine orally despite a lack of evidence for its efficacy by this route of administration. Objectives: To compare systemic and local immune responses following intranasal or oral administration of the USDA-approved, live-attenuated Streptococcus equi subspecies equi vaccine (Pinnacle IN®, Zoetis, Florham Park, New Jersey). Study Design: Experimental, randomized clinical trial Methods: Eight healthy horses with low Streptococcus equi M protein (SeM) titers (<1:1600) were randomly assigned to an intranasal or oral two-vaccine series. SeM-specific serum immunoglobulins G (IgG) and A (IgA) and nasal secretion IgA were assessed using a commercially-available ELISA (Equine Diagnostic Solutions, LLC, Lexington, Kentucky) and a novel magnetic microsphere assay utilizing fluorescence. A general linear mixed models approach was used for statistical data analysis. Results: As expected, intranasal vaccinates showed substantial increases in both serum SeM-specific IgG and IgA levels post-vaccination (P=0.0006 and P=0.007, respectively). Oral vaccinates showed an increase in serum SeM-specific IgG post-vaccination (P=0.0150), though only one-third the magnitude of intranasal vaccinates. Oral vaccinates showed no evidence of change in SeM-specific IgA post-vaccination (P=0.15). Main Limitations: Changes in mucosal antibody responses were not identified in this study which may be related to small change in antibody response, timing of sample collection, or method of nasal secretion collection. Conclusions: Results indicate that intranasal or oral vaccine administration resulted in increased serum SeM-specific IgG, though the magnitude of response differed between routes.
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Hamilton, Andrea. "An investigation of lipoprotein biosynthesis in the equine pathogen Streptococcus equi." Thesis, University of Sunderland, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268974.
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Silva, Mariana Sá e. "COMPARAÇÃO ENTRE TESTES BIOQUÍMICOS E ANÁLISE DA SEQUÊNCIA PARCIAL DO GENE hsp60 PARA A IDENTIFICAÇÃO DE ISOLADOS DE Streptococcus equi." Universidade Federal de Santa Maria, 2005. http://repositorio.ufsm.br/handle/1/10217.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorStreptococcus equi is the etiological agent of strangles. Opportunistic agents from the same group are frequently isolated from horses with strangles and may induce mistake diagnostic. Among the subspecies of S. equi the phenotypic characteristics are almost undistinguishable; however the pathogenic potential is widely differentiated. The objective of this study was to determine the phenotypic and molecular characteristics of S. equi isolates obtained from samples of clinical cases of strangles by sequencing the hsp60 gene. By phenotypical assays 26 strains of Streptococcus sp. were identified, 18 were characterized as S. equi subsp. equi, five as S. equi subsp. zooepidemicus, two as S. dysgalactiae subsp., equisimilis, and one as Streptococcus sp.; However using molecular characterization, 21 isolates were identified as S. equi subsp. equi and five as S. equi subsp. zooepidemicus. The analysis of the hsp60 sequence is a good discriminatory tool and can be useful as a method of differentiation, principally for the characterization of atypical isolates
Streptococcus equi subesp. equi é o agente etiológico da adenite eqüina. Outros agentes pertencentes ao mesmo grupo, como S. equi subesp. zooepidemicus são freqüentemente isolados de animais com sinais de adenite, podendo originar diagnósticos equivocados. As diferenças bioquímicas são pequenas para as subespécies de S. equi, enquanto o potencial virulento é muito diferenciado, havendo, portanto, necessidade de uma correta diferenciação entre os isolados. O presente trabalho teve como objetivo realizar a comparação fenotípica e molecular de isolados de S. equi, obtidos de casos de adenite eqüina, pela análise de seqüências parciais do gene hsp60. De 26 amostras de Streptococcus sp. analisadas, 18 foram bioquimicamente identificadas como S. equi subesp. equi, cinco como S. equi subesp. zooepidemicus, dois isolados S. dysgalactiae subesp. equisimilis e para um isolado não foi possível determinar a espécie. Pela análise das seqüências, 21 isolados foram identificados como S. equi subesp. equi e cinco como S. equi subesp. zooepidemicus. Dentre os isolados utilizados, quatro apresentaram divergência entre os métodos utilizados. A análise de seqüências do gene hsp60 possui um bom poder discriminatório e pode ser um importante método auxiliar na diferenciação de isolados de Streptococcus equi, especialmente para isolados com padrão atípico de fermentação de açucares
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Ribas, Leandro do Monte. "Fatores epidemiológicos associados a doenças respiratórias em potros Puro Sangue Inglês em quatro propriedades na região de Bagé/RS, Brasil." Universidade Federal de Pelotas, 2008. http://repositorio.ufpel.edu.br/handle/ri/2520.
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Previous issue date: 2008-03-10The present study has the objective to evaluate the epidemiologic factors related to respiratory diseases in thoroughbred foals placed in four stud farms around the city of Bagé/RS region, Brazil. Apart from the collection of data linked to breeding management practices, the evaluations consisted of the diary clinical control and complementary examinations for diagnosis using secretions collected from the respiratory tract of the foals affected with respiratory diseases. Among the 349 monitored foals until their 180 days of life, the incidence of 9,5% (33) of respiratory cases with 0,57% (2) of mortality was recorded. The concentration of cases was higher in months of summer, the 120 and 180 days old foals were more susceptible. The occurrence of the diseases was influenced by the breeding system and management practices that increased the environmental contamination potential, and also by the contact among the foals. No clinic case was related to the equine influenza virus (EIV) and to the equine herpesvirus (EHV) pathogens. Among the isolated pathogens, the highest frequency was for Streptococcus equi (57%), followed by Rhodococcus equi (17%) and this one was responsible for 50% of lethality. The obtained results suggest that connected factors to the management in the breeding of thoroughbred equine are going to contribute decisively for the manifestation of the respiratory disease and alert for the high morbidity caused by the equine adenitis and the high lethality related to Rhodococcus equi pathogens.
O presente estudo teve por objetivo avaliar fatores epidemiológicos associados com doenças respiratórias em potros Puro Sangue Inglês (PSI) alojados em 4 propriedades na região da cidade de Bagé-RS, Brasil. Além da coleta de dados ligados ao manejo de criação, as avaliações consistiram no monitoramento clínico diário e exames complementares de diagnóstico a partir de secreções colhidas do trato respiratório de potros com enfermidade respiratória. Entre os 349 potros monitorados até os 180 dias de vida, pôde-se registrar a incidência de 9,5% (33) de casos respiratórios, com mortalidade de 0,57% (2). A concentração de casos foi mais elevada nos meses de verão e potros com idade entre 120 e 180 dias foram mais suscetíveis. A ocorrência de doenças foi influenciada pelo sistema de criação e práticas de manejo que aumentaram o potencial de contaminação do ambiente e o contato entre potros. Nenhum caso clínico foi relacionado ao vírus da influenza (EIV) e ao herpesvírus eqüino (EHV). Entre os isolados, a maior freqüência foi de Streptococcus equi (57%), seguido do Rhodococcus equi (17%), este responsável pela letalidade de 50%. Os resultados sugerem que fatores ligados ao manejo na criação de eqüinos PSI parecem contribuir decisivamente para a manifestação da doença respiratória e alertam para a elevada morbidade causada pela adenite eqüina e a alta letalidade associada à rodococose entre potros jovens (>180 dias).
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Flock, Margareta. "Development of a vaccine against strangles /." Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-500-3/.
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von, Beek Christopher. "Interactions of Streptococcus equi and Mast Cells: In the Search of Virulence Factors." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-347561.
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Mast cells are key players of the innate immune system due to their location at the interface of host and pathogen encounters, such as on mucosal surfaces or the skin. Secreting a variety of compounds, they communicate with other immune cells in a highly specific manner. Subsequently, reinforcements against foreign invaders are recruited while also defending the host, using bacteriolytic effector molecules. One type of pathogens which are competent challengers of the host’s immune system are Streptococci, causing a burden for humans and animals. Streptococcus equi subspecies equi is one example, a highly contagious horse pathogen with a silent carrier subset, causing “strangles”, a disease resulting in equine morbidity and mortality all over the world. The present study aimed to explore the virulence factors in S. equi responsible for immune system activation, represented by mast cells. Knockout mutants of the genes aroB, hasA, pyrC, recA, sagA and a combination of those, including a deletion strain of all superantigens (seeHILM), were co-cultivated with murine bone-marrow-derived mast cells (BMMCs). Mast cells alone and S. equi strain 4047 (wild-type) were used as controls. It was shown that 4 h after encounter of the bacteria, BMMCs responded with IL-6, TNF-α and MCP-1 secretion, indicating an inflammatory response to all strains except against the sagA mutant (ΔsagA) or the multi-deletion strain, the latter lacking several virulence factors including sagA. These results were confirmed at the mRNA-level where IL-6, TNF-α and Nr4a3 gene expression was significantly upregulated in BMMCs after 4 h incubation with wild-type S. equi. In contrast, when BMMCs were co-cultivated with sagA-deficient S. equi, no detectable upregulation was seen. These results were further confirmed in peritoneal-derived mast cells. After 24 h no secretion of cytokines was detected in response to ΔsagA mutants, in contrast to the strong cytokine output in response to wild-type S. equi. To elucidate the role of SagA, the precursor of streptolysin S (SLS), lysis was determined, and it was observed that ΔsagA does not lyse mast cells in contrast to wild-type with intact SLS. Transwell-based experiments indicated a partially contact-dependent response of mast cells to bacteria. Taken together, this study shows for the first time that SLS is the major mast cell activator produced by S. equi. I suggest the possible mechanism of cell death by lysis and reprogrammed signaling pathways of the host by sublytic concentrations of SLS, resulting in damage associated pattern-mediated signaling as well as auto- and paracrine amplification by inflammatory cytokines and other messenger molecules.
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Kirinus, Jackeline Karsten. "Fenotipia e genotipia de Streptococcus equi isolados de equinos da região sul do Brasil." Universidade Federal de Santa Maria, 2010. http://repositorio.ufsm.br/handle/1/10071.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorThe phenotypic characteristics [morphology, biochemical fermentation, antimicrobial susceptibility, index of multiple resistances to antimicrobials (MAR), minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of benzilpenicilin] of 38 Streptococcus equi isolates were evaluated in this study. The phenotypic analyses demonstrated three colony patterns, three carbohydrate fermentation patterns and variation from 0 to 0.4 in the index of multiple resistances to antimicrobials. All the isolates of S. equi demonstrated sensitivity to penicillin, both by the disc diffusion method and microdilution method. The average MIC and MBC for benzilpenincillin were of 0,0095 μg/mL and 0.0267 μg/mL for S. equi subsp. equi and of 0.0128 μg/mL and 0.0380 μg/mL for S. equi subsp. zooepidemicus. The samples of S. equi differed in the values of MIC and MBC (p<0,05). The size of the penicillin inhibition halo demonstrated a relation with the MIC and MBC for S. equi subsp. equi, however for the samples of S. equi subsp. zooepidemicus this relation was only verified with the MBC. The MIC of benzilpenincillin of the samples isolated from the Central, Planalto and South regions of Rio Grande do Sul were statistically similar, although different from the Paraná state sample, suggesting the atypical character of this strain. All S. equi isolates are sensitive to penicillin and sulfazotrim, confirming these as antibiotics of choice for the treatment of infections caused by this agent in the clinical veterinary practice. Genotypic characteristics were also analyzed (hsp60 gene partial sequencing and analysis) in 20 isolates of Streptococcus equi from clinical samples of horses with strangles. The phylogenetic analysis showed a politomy among the isolates, suggesting that the hsp60 gene does not allow the differentiation between S. equi subspecies. New studies are suggested with expansion of territory sampled or even with the application of other markers, in order to clarify the evolutionary patterns not resolved and to confirm or not the real genetic differences between subspecies.
As características fenotípicas [morfológicas, bioquímicas, susceptibilidade aos antimicrobianos, índice de resistência múltipla aos antimicrobianos - IRMA, concentração inibitória mínima (CIM), concentração bactericida mínina (CBM) da benzilpenicilina] de 38 isolados de Streptococcus equi foram avaliadas neste estudo. A fenotipia demonstrou três padrões de colônias, três perfis de fermentação de carboidratos e variação de 0 a 0,4 no índice de resistência múltipla aos antimicrobianos. Todos os isolados de S. equi demonstraram sensibilidade à penicilina, tanto pelo método de disco difusão quanto pelo método de microdiluição. A CIM e CBM média de benzilpenicilina foi de 0,0095 μg/mL e 0,0267 μg/mL para S. equi subesp. equi e de 0,0128 μg/mL e 0,0380 μg/mL para S. equi subesp. zooepidemicus. As amostras de S. equi diferiram para valores de CIM e CBM (p<0,05). O diâmetro do halo de inibição de penicilina demonstrou relação com a CIM e a CBM para S. equi subesp. equi, entretanto para as amostras de S. equi subesp. zooepidemicus esta relação somente foi verificada para a CBM. A CIM de benzilpenicilina frente às amostras isoladas da região Central, Planalto e Sul do estado do Rio Grande do Sul foram estatisticamente semelhantes, mas diferiram do isolado do estado do Paraná, sugerindo o caráter atípico desta cepa. Todos os isolados de S. equi são sensíveis à penicilina e sulfazotrim, antimicrobianos de eleição para as afecções por este agente na clínica veterinária. Também foram analisadas as características genotípicas (sequenciamento parcial e análise do gene hsp60) de 20 isolados de Streptococcus equi oriundos de amostras clínicas de animais com adenite equina. A filogenia mostrou uma politomia entre os isolados, e indicou que este marcador (gene hsp60) não permite a diferenciação das subespécies de S. equi. Sugere-se a realização de novos estudos com a ampliação da região amostrada ou mesmo com a aplicação de outros marcadores, a fim de esclarecer os padrões evolutivos não-resolvidos e confirmar ou não a diferenciação genética real entre as subespécies.
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Moraes, Carina Martins de. "Produção e avaliação de proteína SeM recombinante para o controle de Adenite Equina." Universidade Federal de Pelotas, 2008. http://repositorio.ufpel.edu.br/handle/ri/1268.
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Previous issue date: 2008-10-13Strangles is a contagious disease of the upper respiratory tract of horses caused by Streptococcus equi subsp. equi. Asymptomatic carriers responsible for maintaining the infection in the herd can only be detected by serological or microbiological methods and vaccines used for the control of the disease induce levels of protection generally not exceeding 50%. Considering that S. equi SeM protein is considered the most promising antigen to protect against the disease, this research aimed to produce and evaluate as antigen for vaccines and for ELISA, a recombinant S. equi SeM protein (rSeM). rSeM was produced by cloning and expression in Escherichia coli and purified by affinity chromatography. To test its immunogenicity isogenic female Balb-c mice 4-6 weeks-old were randomly divided and inoculated with 1 / 20th of the estimated dose of the vaccine for horses by the SC route, on days 0 and 21 of the experiment. One group was vaccinated with 250mL (12 mg mL-1) of rSeM without adjuvant, another with 300mL of vaccine containing 12 mg mL-1 of rSeM plus 20% of aluminiun hydroxide, two other groups were vaccinated with two commercial bacterins against Strangles, other two groups were vaccinated with the same commercial vaccines containing 12 mg mL-1 of rSeM and the remaining group was inoculated with a bacterin produced with a field strain. The control group was inoculated the same dose of sterile saline. Blood samples were collected from the retro-orbital venous plexus on days 0, 21, 42. The antibodies were titrated by ELISA using rSeM as antigen. rSeM was immunogenic for mice with a protection index of 100%. For the standardization of an ELISA, groups of 20 negative, vaccinated and positive animals were used. Using as Cut-off the mean plus two SD of the Optical Densities of the negatives, the test showed 100% sensitivity and specificity.
A Adenite Eqüina é uma enfermidade contagiosa do trato respiratório superior dos eqüídeos causada por Streptococcus equi subesp. equi. Animais portadores assintomáticos responsáveis pela permanência da infecção nos rebanhos só podem ser detectados por métodos microbiológicos ou sorológicos e as vacinas utilizadas no controle da doença induzem níveis de proteção geralmente não superiores a 50 %. Considerando que a proteína SeM de S. equi é o antígeno mais promissor na proteção contra a doença, este trabalho objetivou produzir a proteína SeM recombinante de S. equi, visando sua utilização como antígeno em vacinas e em ELISA. Proteína SeM recombinante (rSeM) foi produzida mediante a clonagem e expressão em Escherichia coli e purificada por cromatografia de afinidade. Para testar sua capacidade imunogênica, vacinas elaboradas com rSeM foram aplicadas a camundongos. Fêmeas Balb/c isogênicas com 4-6 semanas foram divididas aleatoriamente e inoculadas por via SC com 1/20 da dose vacinal estimada para cavalos, nos dias 0 e 21 do experimento. Um grupo foi vacinado com 250 mL (12 mg mL-1) de proteína recombinante sem adjuvante, outro com 300 mL de vacina contendo 12 mg mL-1 rSeM adicionada de 20% de hidróxido de alumínio, outros dois grupos com duas bacterinas comerciais contra Adenite Eqüina; dois grupos com as vacinas comerciais, acrescidas de 12 mg mL-1 de rSeM e o grupo restante com uma bacterina contendo cepas de campo. O grupo controle foi inoculado com o mesmo volume de solução salina estéril. Coletou-se sangue por punção do plexo venoso retro-ocular nos dias 0, 21 e 42. Os anticorpos foram titulados por ELISA utilizando a proteína rSeM como antígeno. A rSeM foi imunogênica em camundongos com índices de proteção de 100%. Para a padronização de um ELISA, utilizaram-se grupos de 20 soros equinos de animais negativos, vacinados e positivos. Utilizando um ponto de corte de média das densidades ópticas dos soros negativos acrescidos de dois desvios padrão, o teste teve 100% de sensibilidade e especificidade.
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Ikolo, Felicia. "Characterisation of the PrtM maturase of Streptococcus equi, a proven virulence factor in strangles." Thesis, Northumbria University, 2013. http://nrl.northumbria.ac.uk/15129/.
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Streptococcus equi subspecies equi (S. equi) is the pathogen responsible for the prevalent and highly contagious equine disease called strangles. Strangles has been reported worldwide as a cause of a high level of animal suffering and economic loss. S. equi is susceptible to many antibiotics in vitro, but relapse due to insufficient vascularity often renders such treatment ineffective. Getting effective and universally accepted vaccines against S. equi have been slow mainly because of safety concerns. It was previously reported that colonization of air interface organ cultures, after inoculation with a mutant strain (ΔprtM138-213) deficient in the putative maturase lipoprotein (PrtM, a homologue of the pneumococcal PpmA) was less than that seen in cultures which were infected with wild-type S. equi strain 4047 (Hamilton et al, 2006), indicating that PrtM is a major virulence factor in strangles. It has also been demonstrated by in vitro and in vivo studies that many streptococcal adhesins, for example, serve as colonization or virulence factors and this makes them attractive targets for therapeutic and preventive strategies against streptococcal infections (Nobbs et al., 2009). S. equi adhesins or other colonization factors may be substrates for PrtM. Understanding PrtM is key to designing drugs or vaccines against the equine S. equi infection and strangles. In this research, advanced biomolecular techniques were systematically applied to investigate and characterise PrtM, and to evaluate its potential as a therapeutic or vaccine target. Bioinformatics, microbiological, biochemical and molecular biology techniques were used in screening the S. equi WT 4047 and Mutant (prtM138-213) strains to evaluate the immunogenicity and conservation of PrtM. Proteomics techniques: two-dimensional gel electrophoresis and mass spectrometry were employed in evaluating the cell-associated and secreted protein extracts of both the S. equi WT 4047 and mutant (prtM138-213) strains. In this study, genetic engineering technology involving targeted domain knock-out and/or knock-in, was employed in producing the central domain recombinant protein and mutant (prtM138-213) revertants. Following cloning, over-expression and purification of the full length and central domain, biochemical data on the PrtM protein (kcat/KM for S. equi 4047 PrtM full length recombinant protein = 5.84 x 106 /M/s) were derived via enzyme(peptydylprolyl isomerase - PPIase) assay; and crystallography was applied in an attempt to derive structural data on the PrtM protein. Advanced biomolecular techniques (including Western blots and Proteomics) were employed in screening the complemented mutants. It has been proven from this research that the PrtM of S. equi 4047 is involved in adaptation to NaCl stress and in regulating sensitivity to antibiotics; PrtM may have roles in speeding up the synthesis of hyaluronic acid and in the folding or remodeling of HPr Kinase. The parvulin-type structure of PrtM elucidated by bioinformatics analysis, the cross reactions of the WT and mutant with a number of antisera, the observation that PrtM may be a multisubstrate foldase due to the detectable and significant differences in the proteomes of the WT, mutant and complemented mutants, the dimeric protein formed by the full length recombinant protein of S. equi 4047 WT, and the PPIase-Chaperonine activities of PrtM, all observed from this study, validate PrtM of S. equi 4047 as a viable and novel therapeutic target which pharmaceutical industries should extensively evaluate for the prevention and treatment of S. equi infection and strangles.
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Osičková, Jana. "Řízení molekulové hmotnosti kyseliny hyaluronové (HA) nastavením specifické rychlosti růstu kultury Streptococcus equi subsp. zooepidemicus." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2017. http://www.nusl.cz/ntk/nusl-295654.
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This master thesis focuses on the effect of cultivation parameters on hyaluronic acid synthesis during its biotechnological production. The cultivation parameters were temperature of the cultivation, aeration, agitation, carbon source and addition of phosphatidylcholine. Changes in molecular weight and yield of hyaluronic acid, growth of biomass and medium viscosity were observed. From the obtained data we learned, that the specific growth rate greatly impacts final characteristics of hyaluronic acid. Under suboptimal temperatures a high molecular weight polymer was synthesised along with comparable yields from the control cultivation. High temperatures (40 °C) caused a dip in molecular weight. The next cultivation parameters were aeration and agitation. The highest molecular weights were obtained in cultivations with high agitation rates and intensive aeration, specifically 1 vvm/800 rpm and 2 vvm/800 rpm. Agitation had a bigger influence on molecular weight than aeration. When the carbon source was changed from sucrose to glucose, the lowest molecular weight and yield were obtained. Addition of phosphatidylcholine with concentration 160 mg/l had a positive effect on the cultivation, where the molecular weight grew and biomass growth was higher.
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Röhm, Albert. "Untersuchungen zur Wirksamkeit und Verträglichkeit eines Lebendimpfstoffes gegen die Druse - Equilis StrepE (Intervet International, Niederlande) - an trächtigen und laktierenden Stuten sowie an Absetzfohlen /." Berlin : Mbv, 2008. http://d-nb.info/993024130/04.
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Rebello, Stacey Ann. "Estimation of trimethoprim, sulfamethoxazole, and pentoxifylline concentrations in allantoic fluid of pregnant pony mares with experimentally induced placentitis." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0007221.
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Thesis (M.S.)--University of Florida, 2004.Typescript. Title from title page of source document. Document formatted into pages; contains 186 pages. Includes Vita. Includes bibliographical references.
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Murchie, Tracy Ann. "Measuring gentamicin and penicillin concentrations in allantoic fluid of pregnant pony mares by in vivo microdialysis." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0004906.
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Thesis (M.S.)--University of Florida, 2004.Typescript. Title from title page of source document. Document formatted into pages; contains 152 pages. Includes Vita. Includes bibliographical references.
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Roger, François. "Recherches épidémiologiques et microbiologiques sur une maladie émergente du dromadaire (Camelus dromedarius) dans la Corne de l'Afrique : rôles possibles du virus de la peste des petits ruminants (Paramyxoviridae, Morbillivirus) et de "Streptococcus equi subsp. equi"." Montpellier 2, 2000. http://www.theses.fr/2000MON20216.
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En ethiopie, en 1995 et 1996, une maladie epizootique a touche la majeure partie de la population cameline. C'etait une pathologie aigue tres contagieuse, caracterisee par un syndrome febrile et respiratoire. La morbidite etait tres elevee et la mortalite variable, surtout apres un traitement antibiotique. En moins de deux ans, la maladie a ete enregistree dans toutes les zones d'elevage camelin de la corne de l'afrique. La similitude des symptomes avec ceux de la peste des petits ruminants (ppr), affectant a la meme periode des caprins et ovins des memes zones, et la propagation remarquablement rapide de cette maladie, ont oriente les recherches etiologiques vers une maladie virale et plus precisement vers les morbillivirus des ruminants (virus de peste bovine et de la ppr). Une souche du virus ppr (pprv) a ete detectee par un test d'immunocapture d'antigenes et par amplification genique (rt-pcr). Le sequencage de fragments amplifies a montre une proximite genetique avec des souches connues du virus ppr. Un test elisa pour la detection des anticorps anti-pprv a ete effectue sur des echantillons de serums de regions epidemiologiquement differentes. Une augmentation des taux de sero-prevalence a ete observee. Par ailleurs, des travaux bacteriologiques ont ete conduits en utilisant plusieurs milieux de culture. Une souche de streptococcus equi subsp. Equi a ete isolee. C'etait apparemment le premier isolement de l'agent de la gourme des equides chez des camelides. Il est plausible que cette maladie ait ete initiee par une souche du virus ppr. Ce virus pouvait avoir un role immunosuppresseur favorisant l'apparition d'infections bacteriennes secondaires. Toutefois, considerant la specificite de la gourme des equides, maladie tres contagieuse, le role exact de streptococcus equi subsp. Equi reste a etre evaluer. Ces hypotheses sont discutees, notamment dans le contexte des maladies emergentes et du transfert interespeces d'agents infectieux.
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Hrudíková, Radka. "Vytipování a sledování exprese genů ovlivňujících syntézu kyseliny hyaluronové ve streptococcus equi subsp. zooepidemicus pomocí technologie dna čipů a real time PCR." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2020. http://www.nusl.cz/ntk/nusl-432922.
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Hyaluronic acid (HA) is an important substance, which is mostly used in pharmaceutical and cosmetic industry. This substance is commonly found in the human body. HA is one of the factors contributing to virulence of microorganisms. Some bacterial strains produce hyaluronic acid in the form of a mucoid capsule that encapsulates the cell to protect bacteria against the immune system of the host organism. One of the main producers is the bacterial strain Streptococcus equi subsp. zooepidemicus. Contipro a.s. uses the strain CO4A to produce hyaluronic acid in large scale. The production strain was obtained by random mutagenesis by UV light. The aim of the work was to study changes in the genome, which led to a significant increase in hyaluronic acid production, using DNA microarray and real-time PCR (qPCR). The genome of the strain CO4A was sequenced and compared to reference ATCC35246 [1]. The size of the genome is 2,167,251 bp and 83 relevant variants (59 SNV and 34 indels) have been identified. Variants in coding regions were annotated and amino acid sequence changes were determined. In SNV mutations there was a change in the amino acid sequence in 45 cases. The change was identified in every case of indel mutations. The expression level of selected groups of genes was monitored in both strains by the method of DNA microarrays. A cascade of increased expression level of amino sugar metabolism genes leading to the synthesis of UDP-N-acetyl glucosamine was observed in strain CO4A (the increase in expression level of these genes compared to ATCC35246 was on average 28 %). Subsequently, the expression of selected genes was verified by qPCR. There was no significant difference in the expression level of the has operon genes of both strains. The effect of supplementation of the culture medium with N-acetylglucosamine (GlcNAc), which is one of the precursors of HA synthesis, was also studied by qPCR. A positive effect of the supplementation of the culture medium with external GlcNAc in the CO4A strain has been recorded. Also, the supplementation has positive effect on the yield of HA from the medium (increase in yield was on average by 17 %). GlcNAc has been shown to have a positive effect on the yield of HA in ATCC35246 strain as well (increase in yield was 9 % on average), but no significant changes in the expression levels were found in selected groups of genes in ATCC35246.
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Mandawe, John Verfasser], Ulrich [Akademischer Betreuer] [Schwaneberg, and Lars Mathias [Akademischer Betreuer] Blank. "Engineering of hyaluronic acid synthases from Streptococcus equi subsp. zooepidemicus and Pasteurella multocida towards improved HA chain length and titer / John Mandawe ; Ulrich Schwaneberg, Lars Mathias Blank." Aachen : Universitätsbibliothek der RWTH Aachen, 2018. http://d-nb.info/1181335272/34.
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Mandawe, John [Verfasser], Ulrich [Akademischer Betreuer] Schwaneberg, and Lars Mathias [Akademischer Betreuer] Blank. "Engineering of hyaluronic acid synthases from Streptococcus equi subsp. zooepidemicus and Pasteurella multocida towards improved HA chain length and titer / John Mandawe ; Ulrich Schwaneberg, Lars Mathias Blank." Aachen : Universitätsbibliothek der RWTH Aachen, 2018. http://d-nb.info/1181335272/34.
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Spoerry, Christian. "Streptococcal immunoglobulin degrading enzymes of the IdeS and IgdE family." Doctoral thesis, Umeå universitet, Institutionen för molekylärbiologi (Medicinska fakulteten), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-134552.
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Bacteria of the genus Streptococcus are common asymptomatic colonisers of humans and animals. As opportunistic pathogens they can however, depending on their host’s immune status and other circumstances, cause mild to very severe infections. Streptococci are highly intertwined with specific host species, but can also cause zoonosis or anthroponosis in more uncommon hosts. Prolonged and reoccurring infections require immune evasion strategies to circumvent detection and eradication by the host’s immune defence. A substantial part of the immune defence against bacterial pathogens is mediated by immunoglobulins. This thesis is based on work to identify and characterise immunoglobulin degrading enzymes secreted by different Streptococcus species as a means to sabotage and evade antibody-mediated immune responses. Stoichiometric and kinetic analysis of the IgG degrading enzyme IdeS from the important human pathogen S. pyogenes revealed that IdeS cleaves IgG, opposed to previous publications, as a monomer following classical Michaelis-Menten kinetics. The IdeS homologue of S. suis, IdeSsuis, did however not cleave IgG, but was highly specific fo rporcine IgM. S. suis was found to possess yet another protease, IgdE, capable of cleaving porcine IgG. Both of these proteases were shown to promote increased bacterial survival in porcine blood during certain conditions. IgdE is the founding member of a novel cysteine protease family (C113). Novel streptococcal members of this protease family were shown to specifically degrade certain IgG subtypes of the respective Streptococcus species’ main host. The observed substrate specificity of IgdE family proteases reflects the host tropism of these Streptococcus species, thereby giving insights into host-pathogen co-evolution. The abundance of immunoglobulin degrading enzymes among Streptococcus species indicates the importance of evasion from the antibody mediated immune responses for streptococci. These novel identified immunoglobulin degrading enzymes of the IdeS and IgdE protease families are potential valid vaccine targets and could also be of biotechnological use.
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Harrington, Dean J., I. C. Sutcliffe, and N. Chanter. "The molecular basis of Streptococcus equi infection and disease." 2002. http://hdl.handle.net/10454/11587.
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NoStreptococcus equi is the aetiological agent of strangles, one of the most prevalent diseases of the horse. The animal suffering and economic burden associated with this disease necessitate effective treatment. Current antibiotic therapy is often ineffective and thus recent attention has focused on vaccine development. A systematic understanding of S. equi virulence, leading to the identification of targets to which protective immunity can be directed, is a prerequisite of the development of such a vaccine. Here, the virulence factors of S. equi are reviewed.
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Harrington, Dean J., J. S. Greated, N. Chanter, and I. C. Sutcliffe. "Identification of lipoprotein homologues of pneumococcal PsaA in the equine pathogens Streptococcus equi and Streptococcus zooepidemicus." 2000. http://hdl.handle.net/10454/11589.
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NoStreptococcus equi and Streptococcus zooepidemicus are major etiological agents of upper and lower airway disease in horses. Despite the considerable animal suffering and economic burden associated with these diseases, the factors that contribute to the virulence of these equine pathogens have not been extensively investigated. Here we demonstrate the presence of a homologue of the Streptococcus pneumoniae PsaA protein in both of these equine pathogens. Inhibition of signal peptide processing by the antibiotic globomycin confirmed the lipoprotein nature of the mature proteins, and surface exposure was confirmed by their release from intact cells by mild trypsinolysis.
Project grant 056042 from The Wellcome Trust.
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Sutcliffe, I. C., J. Trigg, and Dean J. Harrington. "Identification of methionine-processed HPr in the equine pathogen Streptococcus equi." 2000. http://hdl.handle.net/10454/11591.
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NoUsing preparative electrophoresis, a low molecular weight protein has been partially purified from a cell extract of the equine pathogen Streptococcus equi susp. equi. N-terminal sequence analysis and Western blotting revealed the protein to be HPr, a central component of the phosphoenolpyruvate:sugar phosphotransferase system (PTS). Interestingly, the only form of the HPr protein detected in S. equi was one with the amino-terminal methionine removed, a modification that has previously been associated with surface localization of streptococcal HPr proteins.
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Harrington, Dean J., I. C. Sutcliffe, M. Haswell, and S. Dixon. "Surface immunolocalisation of HPr in the equine pathogen Streptococcus equi." 2001. http://hdl.handle.net/10454/3147.
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NoWe have investigated the surface localisation of the phosphotransferase system protein HPr in the equine pathogen Streptococcus equi subsp. equi using immunogold localisation and transmission electron microscopy. Like the LppC acid phosphatase lipoprotein, a reference surface antigen, the S. equi HPR could be clearly detected on the surfaces of intact cells. This study is consistent with previous reports that some streptococcal HPr is cell surface associated and suggests that the extracytoplasmic mobilisation and transfer of phosphate groups by streptococci warrant further investigation.
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Dixon, S., M. Haswell, Dean J. Harrington, and I. C. Sutcliffe. "Surface Immunolocalisation of HPr in the Equine Pathogen Streptococcus equi." 2001. http://hdl.handle.net/10454/11588.
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NoWe have investigated the surface localisation of the phosphotransferase system protein HPr in the equine pathogen Streptococcus equi subsp. equi using immunogold localisation and transmission electron microscopy. Like the LppC acid phosphatase lipoprotein, a reference surface antigen, the S. equi HPR could be clearly detected on the surfaces of intact cells. This study is consistent with previous reports that some streptococcal HPr is cell surface associated and suggests that the extracytoplasmic mobilisation and transfer of phosphate groups by streptococci warrant further investigation.
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Hamilton, A., Dean J. Harrington, and I. C. Sutcliffe. "Characterization of acid phosphatase activities in the equine pathogen Streptococcus equi." 2000. http://hdl.handle.net/10454/11590.
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NoAcid phosphatases hydrolyse phosphomonoesters at acidic pH in a variety of physiological contexts. The recently defined class C family of acid phosphatases includes the 32 kDa LppC lipoprotein of Streptococcus equisimilis. To define further the distribution of acid phosphatases in the genus Streptococcus we have examined the equine pathogens Streptococcus equi subsp. equi and Streptococcus equi subsp. zooepidemicus. Whole cell assays indicated that these organisms possess two acid phosphatases with activity optima at pH 5.0 and pH 6.0-6.5 and that only the former of these was, like LppC, resistant to EDTA. Western blotting with a polyclonal anti-LppC antiserum revealed the presence of a cross-reactive 32 kDa protein in both organisms. The cross-reactive protein in S. equi was shown to be a surface accessible lipoprotein as its processing was inhibited by the antibiotic globomycin and it was released from whole cells by treatment with trypsin. The presence of DNA sequences homologous to the S. equisimilis lppC gene were confirmed by PCR. These data strongly suggest that Streptococcus equi subsp. equi and Streptococcus equi subsp. zooepidemicus produce a lipoprotein acid phosphatase homologous to LppC of S. equisimilis.
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Meyer-Hamme, Maria Barbara [Verfasser]. "Rhodococcus equi und Streptococcus equi subsp. zooepidemicus aus Nasentupfern und Tracheobronchialsekret von lungenkranken Fohlen / vorgelegt von Maria Barbara Meyer-Hamme." 2004. http://d-nb.info/972250387/34.
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Figueiredo, Lara Isabel Martins. "Avaliação da integridade e da actividade de antigénios de Streptococcus Equi encapsulados em lipossomas." Master's thesis, 2010. http://hdl.handle.net/10451/5628.
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Tese de mestrado, Bioquímica, Universidade de Lisboa, Faculdade de Ciências, 2010Streptococcus equi subsp. equi é o agente infeccioso da gurma, doença que permanece como uma das mais dispendiosas e disseminadas por todo o mundo, afectando o tracto respiratório de equídeos. Embora S. equi apresente sensibilidade a alguns antibióticos, a prevenção continua a ser a melhor opção uma vez que este tipo de tratamento revela-se na maioria dos casos ineficaz. Durante o período de recobro os animais desenvolvem uma resposta imune protectora principalmente contra a proteína M-“like” (SeM) antifagocítica associada à parede celular. No entanto, a vacinação de cavalos com bacterinas, extractos de S. equi com adjuvantes e mais recentemente, SeM associada a diferentes adjuvantes, não protege eficazmente os animais da infecção por S. equi. Os antigénios produzidos localmente na nasofaringe desempenham um papel muito importante na resposta imune dos animais contra os antigénios de S. equi, fazendo da mucosa nasal uma via de imunização promissora. Os lipossomas foram já descritos como potentes estimuladores da resposta imune das mucosas. O principal objectivo deste trabalho foi o desenvolvimento e caracterização de lipossomas estáveis encapsulando antigénios de S. equi, e avaliar o seu potencial como veículos de entrega de antigénio pela via nasal através das respostas imunes celular, humoral e das mucosas. Os lipossomas encapsulando S. equi foram preparados pelo método de desidratação – reidratação seguido de extrusão e caracterizados quanto ao tamanho, carga superficial e eficácia de encapsulação. A manutenção da integridade dos antigénios após encapsulação foi confirmada por SDS-PAGE. Os lipossomas assim preparados possuíam potencial zeta positivo, diâmetros médios na ordem dos 0,20 μm e eficiência de encapsulação de cerca de 28%. Após administração intranasal estes lipossomas provocaram resposta imune sistémica, com componente humoral e celular assim como resposta imune ao nível da mucosas das mucosas. Este sistema de veiculação de antigénio é apropriado para imunização nasal uma vez que protege o antigénio de degradação e o apresenta de forma eficaz às células apresentadoras de antigénios. Como alternativa aos lipossomas carregados positivamente, lipossomas com carga superficial negativa foram revestidos com quitosano através de incubação. A influência do quitosano na carga superficial dos lipossomas foi também avaliada.
Streptococcus equi subsp. equi (S. equi) is the causative agent of strangles, which is one of the most costly and widespread infectious diseases, affecting the respiratory tract of Equidae. Although S. equi is sensitive to some antibiotics, prevention is still the best option because antibiotic therapy is often ineffective. During the recovery period, horses develop a protective immune response mostly against the antifagocytic cell wall associated M-like protein SeM. However, horse vaccination with bacterins, adjuvanted S. equi extracts and, more recently, SeM associated to different adjuvants, did not protect animals against infection with S. equi. Locally produced nasopharyngeal antibodies play an important role in the immune response of horses to protein antigens of S. equi, suggesting the nasal mucosa as a promising immunization route. Liposomes have been described as potent stimulators of mucosal immune response. The main purpose of the present work was to develop and characterize stable liposomes encapsulating S. equi antigens, and assess their potential as nasal vaccine delivery vehicle for eliciting specific humoral, mucosal and cellular immune responses. S. equi antigens encapsulated liposomes were prepared by dehydration— rehydration method followed by extrusion and fully characterized for their size, surface charge and encapsulation efficiency. Antigen integrity after encapsulation was confirmed by SDS-PAGE. The developed liposomes possessed +12mV zeta potential, an average vesicle size of 0,20 μm and encapsulation efficiency of ∼28%. Following intranasal administration, S. equi extract formulated in liposomes elicited humoral, mucosal and cellular immune responses. This antigen delivery system presents itself as a potential carrier for nasal immunization protecting the antigen from degradation and efficiently presenting it to the antigen presenting cells. As an alternative to positively charged liposomes, negatively charged liposomes were coated with chitosan by simple incubation method. The influence of mucoadhesive polymer chitosan on surface charge was also assessed.
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Hamilton, A., C. Robinson, I. C. Sutcliffe, J. Slater, D. J. Maskell, N. Davis-Poynter, K. Smith, A. S. Waller, and Dean J. Harrington. "Mutation of the Maturase Lipoprotein Attenuates the Virulence of Streptococcus equi to a Greater Extent than Does Loss of General Lipoprotein Lipidation." 2006. http://hdl.handle.net/10454/11575.
Full textAbstract:
NoStreptococcus equi is the causative agent of strangles, a prevalent and highly contagious disease of horses. Despite the animal suffering and economic burden associated with strangles, little is known about the molecular basis of S. equi virulence. Here we have investigated the contributions of a specific lipoprotein and the general lipoprotein processing pathway to the abilities of S. equi to colonize equine epithelial tissues in vitro and to cause disease in both a mouse model and the natural host in vivo. Colonization of air interface organ cultures after they were inoculated with a mutant strain deficient in the maturase lipoprotein ( prtM138-213, with a deletion of nucleotides 138 to 213) was significantly less than that for cultures infected with wild-type S. equi strain 4047 or a mutant strain that was unable to lipidate preprolipoproteins ( lgt190-685). Moreover, mucus production was significantly greater in both wild-type-infected and lgt190-685-infected organ cultures. Both mutants were significantly attenuated compared with the wild-type strain in a mouse model of strangles, although 2 of 30 mice infected with the lgt190-685 mutant did still exhibit signs of disease. In contrast, only the prtM138-213 mutant was significantly attenuated in a pony infection study, with 0 of 5 infected ponies exhibiting pathological signs of strangles compared with 4 of 4 infected with the wild-type and 3 of 5 infected with the lgt190-685 mutant. We believe that this is the first study to evaluate the contribution of lipoproteins to the virulence of a gram-positive pathogen in its natural host. These data suggest that the PrtM lipoprotein is a potential vaccine candidate, and further investigation of its activity and its substrate(s) are warranted.
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Matos, Sandra Cristina Machado de. "Distribuição de exotoxinas em estreptococos dos grupos C e G de Lancefield : comparação entre estirpes responsáveis por infeções no Homem e em animais." Master's thesis, 2013. http://hdl.handle.net/10451/11352.
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Tese de mestrado, Ciências Biofarmacêuticas, Universidade de Lisboa, Faculdade de Farmácia, 2013Tem-se verificado que espécies de GCGS de origem animal e do Homem causam doenças semelhantes às observadas para Streptococcus pyogenes(GAS) e partilham alguns fatores de virulência. Um total de 430 estirpes isoladas de infeção no Homem em Portugal entre 1998 e 2010 [S.dysgalactiae subsp. equisimilis (n=418), S.canis (SC) (n=7) e S.equi subsp. zooepidemicus (SESZ) (n=3)] e de origem animal SDSE, SC, SESZ, S. equi subps. equi (SESE) e S. dysgalactiae subsp. dysgalactiae (SDSD) recolhidas em Portugal, Alemanha, Itália e Japão foram caraterizadas por electroforese em campo pulsado (PFGE), tipagem emm e presença de genes das exotoxinas. Os resultados de PFGE mostraram uma distinção entre estirpes de SDSE de origem animal e humana e entre SDSE e SDSD, sugerindo que a capacidade destas espécies causarem infeção em diferentes hospedeiros é limitada. Ao contrário do observado para SC, SESE e SESZ, as poucas estirpes de infeção no Homem foram indistiguiveis das de origem animal. O gene emm foi amplificado em 99,7% das estirpes SDSE de infeção no Homem, mas em apenas 79,6% das de origem animal. Nenhuma relação do tipo emm com a severidade da infeção foi encontrada. Poucas estirpes de SC também amplificaram o gene emm, mas nenhuma isolada do Homem foi tipável. Novos alelos dos genes das exotoxinas foram encontrados: speG, speA, speC, speI, speH, speL, speM, speF, speK, szeN, szeP e szeF. A maioria das estirpes de SDSE e SC amplificaram o speG, sugerindo uma proximidade genética entre estas espécies e GAS. Concluiu-se que os GCGS poderão ser reservatórios de genes de exotoxinas e estreptodornases que são codificados por profagos de GAS e que podem ser transferidos por transferência horizontal. Uma possível transferência de genes cromossomais também foi observada entre GAS e GCGS e entre estirpes de GCGS.
It has been found that both animal and human GCGS species cause similar diseases to those caused by Streptococcus pyogenes(GAS), as well sharing some virulence factors. A total of 430 strains isolated from Human infections in Portugal between 1998 and 2010 [S.dysgalactiae subsp. equisimilis (n=418), S. canis (SC) (n=7) and S.equi subsp. zooepidemicus (SESZ) (n=3)] and animal strains SDSE, SC, SESZ, S. equi subsp. equi (SESE) and S. dysgalactiae subsp. dysglactiae (SDSD) isolated from Portugal, Germany, Italy and Japan were characterized by pulsed-field gel electrophoresis (PFGE), emm typing and tested for the presence of exotoxin coding genes. The PFGE results showed distinction between animal and human SDSE strains, as well as between SDSE and SDSD, suggesting that the ability to cause infection in diferent hosts is limited. In contrast for SC as well as SESZ the few human infection strains were indistinguishable from those of animal infections. The emm gene was found in 99,7% of SDSE strains of Human infections, but only 79,6% of animal SDSE isolates amplified this gene. No relationship of emm type with infection severity was found. Few SC strains also amplified this gene, but none of the human isolates could be emm typed. New alleles of several exotoxin genes were found: speG, speA, speC, speI, speH, speL, speM, speF, speK, szeN, szeP and szeF. Most SDSE and SC strains amplified a speG-like gene, suggesting a genetic proximity between the two species and with GAS. It was concluded that GCGS species may be reservoirs of exotoxins and streptodornases genes, which are encoded by GAS prophages and that can be transferred by horizontal gene transfer. Possible chromosomal gene transfers were also identified between GAS and GCGS as well as between GCGS strains of animal and human origin.
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Florindo. "Development of alternative micro and nanoparticulate polymeric systems for mucosal delivery of Streptococcus equi antigens." Doctoral thesis, 2008. http://hdl.handle.net/10451/262.
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Tese de doutoramento em Farmácia (Tecnologia Farmacêutica), apresentada à Universidade de Lisboa através da Faculdade de Farmácia, 2008S. equi is considered the causative agent of strangles, a very contagious disease of the upper respiratory tract of the Equidae. Although S. equi is sensitive to some antibiotics, most of the current treatments are ineffective. During the recovery period, horses develop a protective immune response mostly against the antiphagocytic cell wall-associated M-like protein SeM, which encourages the development of efficient vaccines. The main purpose of this thesis was to develop and characterise stable polymeric particles and study their potential as mucosal S. equi antigens adjuvant. Non-aggregated and easily dispersible micro and nanospheres based on poly-e-caprolactone (PCL) and poly(lactic acid) (PLA) polymers were formulated by the double emulsion (w/o/w) solvent evaporation method and fully characterised. BALB/c monocyte macrophages (cell line J774.1A) were used in toxicity tests and cellular uptake studies. The influence of mucoadhesive polymers (chitosan (CS), glycolchitosan (GCS) and alginate (ALG)) and absorption enhancers (spermine (SP) and oleic acid (OA)) in particle physicochemical characteristics and consequently in the humoral, mucosal and cellular immune responses was as well evaluated. The non-toxic cholera toxin B subunit (CTB) is a potent mucosal adjuvant, and the oligodeoxynuleotide with repeating C and G motives (CpG) can also be used to up-regulate mucosal and cellular immune responses, increasing preferentially the T helper type 1 (Th1) cell activity. Therefore, those adjuvants were co-administrated with soluble antigen and non-modified PLA and PCL particles, in order to assess their eventual synergic effect. Inspite of administration route (i.n. and i.m.), S. equi-loaded polymeric systems were able to significantly increase systemic and cellular immune responses, when compared with free antigens, isolated or co-admixed with CTB or CpG. PLA-loaded particles generally induced higher mucosal antibody levels when compared with the correspondent PCL. Similar results were attained when the immune responses induced by S. equi antigens-adsorbed particles were compared with those elicited by the correspondent entrapped ones. As per PCL nanospheres, those formulated with ALG and GCS, seem to induce a more balance Th1/Th2 immune response. This study also confirmed the potential adjuvant of S. equi antigen-loaded PLA nanospheres, and again the mucopolysaccharide GCS induced the most prominent immune response. SeM recombinant proteins were entrapped in PLA nanospheres and their adjuvant potential after i.m. administration in a mouse model was compared with that achieved with S. equi extract. In fact, it was possible to observe that PLA-GCS and PLA-OA nanospheres are alternative cost-effective preparations, able to induce a balanced IgG2a/IgG1 immune response. These studies bring new insights into the strangles prevention field as the particulate carriers developed during this PhD thesis, mainly those containing GCS, are promising adjuvants for a safe vaccine against strangles, with no toxicity issues associated to their utilisation, in contrast to other adjuvants that have been associated to S. equi antigens. Therefore, the main goal of this thesis was accomplished but challenge studies must be done in order to support their future utilisation.
Fundação para a Ciência e Tecnologia (FCT) e FEDER (SFRH/BD/14370/2003, POCI/BIO/59147/2004 e PPCDT/BIO/59147/2004)
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Hou, Chien-meng, and 侯建蒙. "The Effect of Added Agents on Hyaluronic Acid Production by Streptococcus equi subsp. zooepidemicus HAWU." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/13167063671156050919.
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碩士大葉大學
生物產業科技學系
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Hyaluronic acid (HA) is a high molecular-weight polymer with repeating units of D-glucuronic acid and N-acetylglucosamine that are bound by alternating β-1,3 and β-1,4 bonds. Because of it’s special biocompatibility and moister-holding function. It has been used as biomedical, cosmetic industry and else relevance field. Commercially, HA is produced through extraction from rooster combs or by microbial fermentation, but problems with this material include the likelihood of it being contaminated by viruses. The main aim of the research was to determine the effect of added agents on hyaluronic acid production by streptococcus equi subsp. zooepidemicus HAWU. The description of this divided in to third sections. The first section is focused on the effect of added agents (lactic acid, Soya beans extract, H2O2) on the production of HA by S. equi subsp. zooepidemicus HAWU. in the flask and 5-L jas ferentor. In the flask, the optimal temperature was 37℃, which led to highest HA production (4.58 g/L). In a 5-L jar fermentor, we achieved maximum HA productivity (1.0 g/h/L) when the added agents. The second section is focused on the empirical kinetic model for the batch production of HA from S. equi subsp. zooepidemicus HAWU. By using Momod and Michaelis- Meten models, it was found that substrate inhibition for HA production when H2O2 was greater than 1 μmolg/L. Morevorer, a model involved with S. equi subsp. zooepidemicus HAWU growth, and HA accumulation combined non- growth- associated and growth- associated contributions, and consumprion of glucose on the logistic and Luedeking- piret equation was developed. The results predicted by the model were good agreement with the experimental observations. The third section is focused on the potential applications of HA as humectant was also study in this research and, the results show that HA has high moisture-absorption and moisture-retention capacities.
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Ikolo, F., M. Zhang, Dean J. Harrington, C. Robinson, A. S. Waller, I. C. Sutcliffe, and G. W. Black. "Characterisation of SEQ0694 (PrsA/PrtM) of Streptococcus equi as a functional peptidyl-prolyl isomerase affecting multiple secreted protein substrates." 2015. http://hdl.handle.net/10454/10324.
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YesPeptidyl-prolyl isomerase (PPIase) lipoproteins have been shown to influence the virulence of a number of Gram-positive bacterial human and animal pathogens, most likely through facilitating the folding of cell envelope and secreted virulence factors. Here, we used a proteomic approach to demonstrate that the Streptococcus equi PPIase SEQ0694 alters the production of multiple secreted proteins, including at least two putative virulence factors (FNE and IdeE2). We demonstrate also that, despite some unusual sequence features, recombinant SEQ0694 and its central parvulin domain are functional PPIases. These data add to our knowledge of the mechanisms by which lipoprotein PPIases contribute to the virulence of streptococcal pathogens.
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"Characterization and evaluation of cross reactivity of strains of Streptococcus equi recovered from horses in shouthern Rio Grande do Sul, Brazil." Tese, Biblioteca Digital da Universidade Federal de Pelotas, 2005. http://www.ufpel.edu.br/tede/tde_busca/arquivo.php?codArquivo=247.
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Hamilton, A., C. Robinson, I. C. Sutcliffe, I. Slater, D. J. Maskell, K. Smith, A. Waller, and Dean J. Harrington. "Mutation of the maturase lipoprotein attenuates the virulence of Streptococcus equi to a greater extent than does loss of general lipoprotein lipidation." 2006. http://hdl.handle.net/10454/3806.
Full textAbstract:
Streptococcus equi is the causative agent of strangles, a prevalent and highly contagious disease of horses. Despite the animal suffering and economic burden associated with strangles, little is known about the molecular basis of S. equi virulence. Here we have investigated the contributions of a specific lipoprotein and the general lipoprotein processing pathway to the abilities of S. equi to colonize equine epithelial tissues in vitro and to cause disease in both a mouse model and the natural host in vivo. Colonization of air interface organ cultures after they were inoculated with a mutant strain deficient in the maturase lipoprotein (prtM138-213, with a deletion of nucleotides 138 to 213) was significantly less than that for cultures infected with wild-type S. equi strain 4047 or a mutant strain that was unable to lipidate preprolipoproteins (lgt190-685). Moreover, mucus production was significantly greater in both wild-type-infected and lgt190-685-infected organ cultures. Both mutants were significantly attenuated compared with the wild-type strain in a mouse model of strangles, although 2 of 30 mice infected with the lgt190-685 mutant did still exhibit signs of disease. In contrast, only the prtM138-213 mutant was significantly attenuated in a pony infection study, with 0 of 5 infected ponies exhibiting pathological signs of strangles compared with 4 of 4 infected with the wild-type and 3 of 5 infected with the lgt190-685 mutant. We believe that this is the first study to evaluate the contribution of lipoproteins to the virulence of a gram-positive pathogen in its natural host. These data suggest that the PrtM lipoprotein is a potential vaccine candidate, and further investigation of its activity and its substrate(s) are warranted.