ANSES, Ploufragan-Plouzané-Niort Laboratory, 22440 Ploufragan, France.
INSERM, CHU Limoges, RESINFIT, U1092, University of Limoges, Limoges, France.
Vet Microbiol. 2020 Apr;243:108619. doi: 10.1016/j.vetmic.2020.108619. Epub 2020 Feb 28.
Antimicrobial resistance is a "One Health" issue that requires improved knowledge of the presence and abundance of resistant bacteria in the environment. Extended-spectrum cephalosporins (ESCs) are critically important antibiotics (CIAs), and resistance to these CIAs is often encoded by beta-lactamase genes borne on conjugative plasmids. We thus decided to characterise 21 plasmids of ESC-resistant Escherichia coli randomly selected from isolates previously obtained from river water collected in a rural area in western France. The plasmids encoding ESC resistance were sequenced to investigate the diversity of the genes encoding ESC resistance and their genetic context. Sequences revealed that eleven IncI1 pMLST3 plasmids carried the bla and sul2 genes, and some of them also had the tet(A), aadA5 or dfrA17 genes. The bla gene was also detected on an IncN plasmid. Five plasmids obtained from four rivers contained bla, either on IncI1 or on IncFII plasmids. Two strains from two rivers contained bla on IncN pMLST7 plasmids, with qnrS1 and dfrA14 genes. One plasmid contained the bla, a bla-like, and fosA genes. One plasmid contained the bla gene. The diversity of the genes and plasmids of the resistant bacteria isolated from French rivers is probably related to the various animal and human origins of the isolated bacteria.
抗微生物药物耐药性是一个“同一健康”问题，需要提高对环境中耐药细菌的存在和丰度的认识。 扩展谱头孢菌素（ESC）是非常重要的抗生素（CIA），而对这些 CIA 的耐药性通常由携带在可接合质粒上的β-内酰胺酶基因编码。因此，我们决定对从法国西部农村地区采集的河水样本中分离出的 21 株 ESC 耐药大肠杆菌随机选择的 21 个质粒进行特征描述。对编码 ESC 耐药性的质粒进行测序，以研究编码 ESC 耐药性的基因及其遗传背景的多样性。序列分析揭示，11 个 IncI1 pMLST3 质粒携带 bla 和 sul2 基因，其中一些还带有 tet(A)、aadA5 或 dfrA17 基因。bla 基因也在一个 IncN 质粒上检测到。从四条河流中获得的五个质粒含有 bla，要么在 IncI1 上，要么在 IncFII 质粒上。两条河流中的两个菌株含有 bla，位于 IncN pMLST7 质粒上，同时带有 qnrS1 和 dfrA14 基因。一个质粒包含 bla、bla-like 和 fosA 基因。一个质粒含有 bla 基因。从法国河流中分离出的耐药菌的基因和质粒多样性可能与分离菌的各种动物和人类来源有关。
