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Impact of the Priobiotic on the Presence of Selected Virulence Genes and Drug-Resistance Among Campylobacter Coli Isolated from Piglets

References 1. Andrzejewska M., Klawe J.J., Szczepańska B., Śpica D.: Occurrence of virulence genes among Campylobacter jejuni and Campylobacter coli isolates from domestic animals and children. Polish J Vet Sci 2011, 2 , 207-211. 2. Bang D.D., Scheutz F., Ahrens P., Pedersen K., Blom J., Madsen M.: Prevalence of cytolethal distending toxin (cdt) genes and CDT production in Campylobacter spp. isolated from Danish broilers. J Med Microbiol 2001, 50 , 1087-1094. 3. Carvalho A.C., Ruiz-Palacios G

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Prevalence of virulence markers and pHS-2-like plasmids among Shigella sonnei and Shigella flexneri isolates originating from shigellosis cases in Romania

: serodiversity, virulence genes, and antimicrobial resistance. J Infect Dev Ctries. 2014 Jul 14;8(7):904-8. DOI: 10.3855/jidc.3692 23. Roy S, Thanasekaran K, Dutta Roy AR, Sehgal SC. Distribution of Shigella enterotoxin genes and secreted autotransporter toxin gene among diverse species and serotypes of shigella isolated from Andaman Islands, India. Trop Med Int Health. 2006 Nov;11(11):1694-8. DOI: 10.1111/j.1365-3156.2006.01723.x 24. Al-Hasani K, Rajakumar K, Bulach D, Robins-Browne R, Adler B, Sakellaris H. Genetic organization of the she pathogenicity island in

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In silico analysis of virulence associated genes in genomes of Escherichia coli strains causing colibacillosis in poultry

Abstract

Introduction: Colibacillosis – the most common disease of poultry, is caused mainly by avian pathogenic Escherichia coli (APEC). However, thus far, no pattern to the molecular basis of the pathogenicity of these bacteria has been established beyond dispute. In this study, genomes of APEC were investigated to ascribe importance and explore the distribution of 16 genes recognised as their virulence factors.

Material and Methods: A total of 14 pathogenic for poultry E. coli strains were isolated, and their DNA was sequenced, assembled de novo, and annotated. Amino acid sequences from these bacteria and an additional 16 freely available APEC amino acid sequences were analysed with the DIFFIND tool to define their virulence factors.

Results: The DIFFIND tool enabled quick, reliable, and convenient assessment of the differences between compared amino acid sequences from bacterial genomes. The presence of 16 protein sequences indicated as pathogenicity factors in poultry resulted in the generation of a heatmap which categorises genomes in terms of the existence and similarity of the analysed protein sequences.

Conclusion: The proposed method of detection of virulence factors using the capabilities of the DIFFIND tool may be useful in the analysis of similarities of E. coli and other sequences deriving from bacteria. Phylogenetic analysis resulted in reliable segregation of 30 APEC strains into five main clusters containing various virulence associated genes (VAGs).

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Virulence factors and antibiotic resistance of avian pathogenic Escherichia coli in eastern China

(also facilitating attachment of APEC to extraintestinal tracts and assisting penetration of bacteria into the tissues), toxins (protecting APEC from lysosomes), siderophores (chelating iron), and protectins (inhibiting the classical pathway of complement activity), which help the bacterial infection to become established and augment the bacterium’s resistance to the host’s immune defences. Epidemic data show that human extraintestinal pathogenic E. coli (ExPEC) strains and APEC often carry similar virulence genes, suggesting the zoonotic importance of APEC strains

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The frequency of shiga-like toxin (stx1 and stx2) and EHEC-hlyA in food by multiplex PCR

enteropathogenic Escherichia coli (EPEC) in raw yak (Poephagus grunniens) milk and milk products. Res Vet Sci. 2012;93(2):604-10. DOI: 10.1016/j.rvsc.2011.12.011 13. Russo LM, Melton-Celsa AR, Smith MJ, O’Brien AD. Comparisons of native Shiga toxins (Stxs) type 1 and 2 with chimeric toxins indicate that the source of the binding subunit dictates degree of toxicity. PLoS One 2014;9:e93463. DOI: 10.1371/journal.pone.0093463 14. Bai J, Shi X, Nagaraja TG. A multiplex PCR procedure for the detection of six major virulence genes in Escherichia coli O

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Typing of Listeria Monocytogenes Isolated from Slaughtered Cattle and Beef Meat

Abstract

A total of 135 L. monocytogenes strains isolated from slaughtered cattle and beef meat were tested by the pulsed field gel electrophoresis (PFGE). The AscI restriction analysis revealed a genetic heterogeneity among investigated isolates since 31, 9, and 35 profiles were distinguished among hide, carcass, and meat strains, respectively. The PFGE profiles of the isolates were also analysed in relation to serotypes, virulence genes, and antimicrobial resistance. It was shown that strains displaying the same PFGE type were of the same serotype while correlation between pulsotype and antimicrobial resistance was poor. The obtained results suggest that a cross-contamination between bovine hides and carcasses may occur during the slaughter process. Moreover, identification of identical PFGE types among L. monocytogenes found during a study period may suggest a common source of contamination or presence of persistent strains able to survive for a long time. These results emphasise the importance of molecular subtyping methods, including PFGE, in monitoring and tracking pathogen contamination along food chain.

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xTAG Luminex multiplex assay for rapid screening of verocytotoxin-producing Escherichia coli strains

Abstract

The O26 verocytotoxin-producing Escherichia coli (VTEC)-associated outbreak of hemolytic uremic syndrome (HUS) cases in Romania during 2016 showed the need to improve the current methodology of non-O157 VTEC detection and surveillance. An in-house assay based on xTAG Luminex technology was optimized to identify seven of the most relevant diarrheagenic E.coli serogroups (O-specific wzx genes), two convenient VTEC virulence markers (eaeA and ehxA genes), and a species-specific control gene (uidA). Twenty-nine strains previously characterized in terms of serogroup and virulence genes were tested with the optimized protocol and the results were as expected. The ratio of sample signal to background varied from 66.7 (ehxA) to 7.6 (uidA) for positive samples, with a cut-off of 3. Sensitivity varied depending on the target to be amplified from approximately 102 genomic copies to approximately 104 genomic copies per reaction, respectively. The current approach seems an affordable alternative to commercially available assays that can be further exploited to improve existing autochthonous strategies to prevent future VTEC outbreaks.

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Monitoring of Selected Genes in Campylobacter Jejuni and Campylobacter Coli Isolates from Domestic Animals

References 1. Andrzejewska M., Klawe J.J., Szczepańska B., Śpica D.: Occurrence of virulence genes among Campylobacter jejuni and Campylobacter coli isolates from domestic animals and children. Pol J Vet Sci 2011, 2 , 207-211. 2. Bang D.D., Scheutz F., Ahrens P., Pedersen K., Blom J., Madsen M.: Prevalence of cytolethal distending toxin (cdt) genes and CDT production in Campylobacter spp. isolated from Danish broilers. J Med Microbiol 2001, 50 , 1087-1094. 3. Carvalho A.C., Ruiz-Palacios G

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Genotypic virulence markers of Yersinia enterocolitica O:9 isolated from pigs and wild boars serologically positive and negative for brucellosis

-744. 9. Jungersen G., Sorensen V., Giese S.B., Stack A., Riber U.: Differentiation between serological responses to Brucella suis and Yersinia enterocolitica serotype O:9 after natural or experimental infection in pigs. Epidemiol Infect 2006, 134, 347-357. 10. Kot B., Piechota M., Jakubczak A.: Analysis of occurrence of virulence genes among Yersinia enterocolitica isolates belonging to different biotypes and serotypes. Pol J Vet Sci 2010, 13, 13-19. 11. Kot B.: Chromosomally and plasmid-encoded virulence determinants of Y

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Genotypic Markers of Yersinia Enterocolitica O:9 Isolated from Cows Positive in Serological Examination for Bovine Brucellosis

by immunomagnetic separation, nested polymerase chain reactions and colorimetric detection of amplified DNA. Appl Environ Microbiol 1993, 59 , 2938-2944. 9. Kot B., Piechota M., Jakubczak A.: Analysis of occurrence of virulence genes among Yersinia enterocolitica isolates belonging to different biotypes and serotypes. Pol J Vet Sci 2010, 13 , 13-19. 10. Kot B.: Chromosomally and plasmid-encoded virulence determinants of Y. enterocolitica. Medycyna Wet 2010, 66, 294-298. 11. Lubeck P.S., Skurnik M., Akrens

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