Cyoia Paula Signolfi, Koga Vanessa Lumi, Nishio Erick Kenji, Houle Sébastien, Dozois Charles M, de Brito Kelly Cristina Tagliari, de Brito Benito Guimarães, Nakazato Gerson, Kobayashi Renata Katsuko Takayama
Department of Microbiology, Center of Sciences Biological, Universidade Estadual de Londrina, Londrina, Brazil.
Institut Armand-Frappier, Institut National de la Recherche Scientifique, Laval, QC, Canada.
Front Microbiol. 2019 Jan 14;9:3254. doi: 10.3389/fmicb.2018.03254. eCollection 2018.
Pathogenic found in humans and poultry carcasses harbor similar virulence and resistance genes. The present study aimed to analyze the distribution of extraintestinal pathogenic (ExPEC) virulence factors (VF), groups, A3, and -1 genes in isolated from commercialized chicken carcasses in southern Brazil and to evaluate their pathogenic risk. A total of 409 strains were isolated and characterized for genes encoding virulence factors described in ExPEC. Results of antimicrobial susceptibility testing confirmed that the strains were resistant to β-lactams, fosfomycin, colistin, and others resistance groups. The highest prevalence of VFs was observed in isolates belonging to the CTX-M groups, especially the CTX-M-2 group, when compared to those in other susceptible strains or strains with different mechanisms of resistance. Furthermore, ESBL strains were found to be 1.40 times more likely to contain three to five ExPEC virulence genes than non-ESBL strains. Our findings revealed the successful conjugation between ESBL-producing isolated from chicken carcass and the recipient strain J53, which suggested that genetic determinants encoding CTX-M enzymes may have originated from animals and could be transmitted to humans via food chain. In summary, chicken meat is a potential reservoir of MDR strains harboring resistance and virulence genes that could pose serious risks to human public health.
在人类和家禽尸体中发现的致病性大肠杆菌携带相似的毒力和耐药基因。本研究旨在分析从巴西南部商业化鸡尸体中分离出的肠外致病性大肠杆菌（ExPEC）的毒力因子（VF）、血清群、A3和F1基因的分布情况，并评估其致病风险。共分离出409株大肠杆菌菌株，并对ExPEC中描述的毒力因子编码基因进行了鉴定。抗菌药敏试验结果证实，这些菌株对β-内酰胺类、磷霉素、黏菌素和其他耐药组具有抗性。与其他敏感菌株或具有不同耐药机制的菌株相比，在属于CTX-M血清群的分离株中观察到毒力因子的最高流行率，尤其是CTX-M-2血清群。此外，发现产ESBL菌株比非产ESBL菌株含有三到五个ExPEC毒力基因的可能性高1.40倍。我们的研究结果揭示了从鸡尸体中分离出的产ESBL大肠杆菌与受体菌株J53之间成功的接合，这表明编码CTX-M酶的遗传决定因素可能起源于动物，并可能通过食物链传播给人类。总之，鸡肉是携带耐药性和毒力基因的多重耐药大肠杆菌菌株的潜在储存库，可能对人类公共健康构成严重风险。
