RESUMO

INTRODUCTION: Campylobacter jejuni is one of the most common bacterial causes of human gastroenteritis. Despite its public health importance, the virulence factors and mechanisms underlying C. jejuni pathogenesis remain poorly understood and the relationships between these genes and the sources of the strains are not clear. We aimed to determine the virulence profiles of C. jejuni isolated from poultry and human cases of Campylobacteriosis. METHODOLOGY: A total of 50 strains of C. jejuni isolated from poultry and human cases of Campylobacteriosis were screened by polymerase chain reaction (PCR) for the presence of six pathogenic genes (flaA, iam, wlaN, cdtA, cdtB, cdtC). RESULTS: A total of 40% (10/25) of the human isolates presented only one virulence marker. In contrast, 64% (16/25) of the poultry-derived strains showed four or five virulence markers. cdtA and flaA occurred more frequently in poultry-derived strains than in human strains. Ten different virulence profiles were observed among the human isolates and 11 among the poultry strains. Only four profiles were common to both sources: profiles 3 (flaA, cdtA, cdtB, and cdtC), 5 (cdtA and cdtB), 7 (flaA and cdtB), and 10 (iam, flaA, cdtA, cdtB, and cdtC). The human-derived strains had a higher Shannon diversity index (1.9396) and Simpson index (0.8367), indicating a more diversified population than found in poultry (1.7742 and 0.7333, respectively). CONCLUSIONS: We found variations in the genetic profiles of the circulating strains based on the isolation source and genes that are potentially pathogenic to humans were detected in poultry-derived strains.

Assuntos

Infecções por Campylobacter , Campylobacter jejuni , Campylobacter , Gastroenterite , Animais , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/veterinária , Campylobacter jejuni/genética , Ácido Edético/análogos & derivados , Humanos , Aves Domésticas/microbiologia , Prevalência , Fatores de Virulência/genética

RESUMO

BACKGROUND: As for human trichomoniasis the host-parasite relationship is very complex, and the broad ranges of clinical symptoms are unlikely be attributable to a single pathogenic mechanism. Specific Random Amplified Polymorphic DNA (RAPD) markers of 490 bp, 720 bp and 460 bp using the primers Tv-5, OPA-6 and OPA-11, respectively, were reported. This was the first description of possible genetic virulence markers of the infection by T. vaginalis. The aim of this study was to characterize the specific RAPD markers in order to elucidate their importance on virulence of this illness. METHODS: The selected specific RAPD fragments were cloned and sequenced. The obtained sequences were compared by the BLAST algorithm. RESULTS: The nucleotide sequence of the Tv-5490 RAPD marker exhibited significant similarity to T. vaginalis hypothetical G3 leucine rich repeat (LRR) family protein (e-value: 6e-14) and Giardia lamblia leucine rich repeat protein 1 virus receptor protein (e-value: 6e-14 and 2e-12) ; however, the OPA-6720 and OPA-11460 showed no significant similarity with any coding published sequence. All the evaluated strains showed the presence of the LRR gene. CONCLUSION: These results demonstrate a possible role of this gene in the virulence of T. vaginalis and in the parasite infection with Trichomonas virus as a possible virus receptor. Further analysis of this gene and encoded protein will allow determining the role that they play in the isolates virus susceptible or resistant phenotypes.