The aim of present study is to characterize the resistance and virulence profile of enterococci isolated from aquaculture excavated ponds and masonry tanks (6 samples) in southern Brazil. Samples were cultured in selective medium, 10 colonies were randomly selected from each sample, which were identified by MALDI-TOF and tested against 13 antimicrobials. The presence of resistance (tetL, tetM, tetS, ermB and msrC) and virulence (ace, esp, agg, cylA and gelE) genes were determined by PCR. A total of 79 enterococci were identified, and Entecococcus faecalis (44.3%) and E. casseliflavus (36.7%) were the most prevalent species isolated. Sixty-five strains (82.3%) were resistant to at least one of the antimicrobials tested, whereas 27 (34.2%) strains were multiresistant. The overall percentages of antimicrobial resistant isolates were: 58.2% to rifampicin, 40.5% to fluoroquinolones, 36.7% to erythromycin and 30.4% to tetracycline. The tetL and tetM genes were found in 57.7% of the tetracycline-resistant strains; and msrC in 31.01% of erythromycin-resistant strains. The most frequently detected virulence factors were ace and gelE genes. Although limited to a single farm, these data suggest that aquaculture may be a reservoir of resistant and virulent enterococci. This study is the first step towards enhancing our understandingof distribution, resistance and virulence profile in enterococci isolated from fish farming environments in the south Brazil.

中文翻译：

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肠球菌的鉴定。与巴西南部的鱼类养殖环境隔离

本研究的目的是表征从巴西南部的水产养殖挖出的池塘和石工池（6个样品）中分离出的肠球菌的抗性和毒力特征。将样品在选择性培养基中培养，从每个样品中随机选择10个菌落，通过MALDI-TOF进行鉴定，并针对13种抗菌素进行测试。通过PCR确定抗性（tetL，tetM，tetS，ermB和msrC）和毒力（ace，esp，agg，cylA和gelE）基因的存在。总共鉴定出79个肠球菌，其中粪肠球菌（44.3％）和卡塞尔大肠杆菌（36.7％）是最常见的菌种。65株（82.3％）对至少一种测试的抗生素有抗药性，而27株（34.2％）对多药具有抗药性。抗菌素耐药菌的总百分比为：58。利福平占2％，氟喹诺酮类占40.5％，红霉素占36.7％，四环素占30.4％。发现tetL和tetM基因的耐药率为57.7％。和31.01％的红霉素耐药菌株中的msrC。最常见的毒力因子是ace和gelE基因。尽管仅限于单个农场，但这些数据表明，水产养殖可能是抗药性和强力肠球菌的蓄水池。这项研究是增强我们对巴西南部鱼类养殖环境中分离的肠球菌的分布，耐药性和毒力分布的了解的第一步。最常见的毒力因子是ace和gelE基因。尽管仅限于单个农场，但这些数据表明，水产养殖可能是抗药性和强力肠球菌的蓄水池。这项研究是增强我们对巴西南部鱼类养殖环境中分离的肠球菌的分布，耐药性和毒力分布的了解的第一步。最常见的毒力因子是ace和gelE基因。尽管仅限于单个农场，但这些数据表明，水产养殖可能是抗药性和强力肠球菌的蓄水池。这项研究是增强我们对巴西南部鱼类养殖环境中分离的肠球菌的分布，耐药性和毒力分布的了解的第一步。