Facultad de Farmacia y Bioquímica, Instituto de Investigaciones en Bacteriología y Virología Molecular, Universidad de Buenos Aires, Junín 956, (1113), Buenos Aires, Argentina.
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2290 (1425), Buenos Aires, Argentina.
Arch Virol. 2021 May;166(5):1337-1344. doi: 10.1007/s00705-021-05024-y. Epub 2021 Mar 8.
A reservoir of antibiotic resistance genes (ARGs) is present in pathogenic, commensal, and environmental bacteria as well as in mobile genetic elements, including bacteriophages. Wastewater treatment plants (WWTPs) are considered hotspots for the spread of ARGs. The aim of this work was to analyze the diversity of the highly prevalent ARGs bla and bla in bacterial and bacteriophage fractions associated with human and animal environments through the study of urban waste and animal residues discharged into WWTPs to provide information about the composition and maintenance of the current resistome in Buenos Aires, Argentina. The results showed that a putative extended-spectrum variant of the bla gene was the most frequently detected, with bla being the most prevalent, while a recently described type, bla, was also found. In the bacteriophage fraction, we detected bla genes from four out of the five clusters described. The detection of bla-like and bla-like genes was unexpected based on surveys of the ARGs from clinical pathogens circulating regionally. The finding of divergent bla sequences associated with previously reported environmental genes argues in favor of the natural environment as a reservoir of resistance genes. ARGs were detected in bacteriophages as frequently as in bacterial communities, and furthermore, the bla genes were more diverse in the bacteriophage fraction. Bacteriophages might therefore play a role in the spread of ARGs in the environment, but they might also be used as "reporters" for monitoring circulating ARGs.
抗生素耐药基因（ARGs）库存在致病菌、共生菌和环境细菌以及移动遗传元件（包括噬菌体）中。污水处理厂（WWTP）被认为是 ARGs 传播的热点。本研究旨在通过研究排入 WWTP 的城市废物和动物残渣，分析与人类和动物环境相关的细菌和噬菌体部分中高度流行的 ARG bla 和 bla 的多样性，为了解阿根廷布宜诺斯艾利斯当前耐药组的组成和维持提供信息。结果表明，检测到的 bla 基因的一种推定的扩展谱变体最为常见，bla 是最常见的，而最近描述的 bla 类型也被发现。在噬菌体部分，我们从描述的五个簇中的四个簇中检测到了 bla 基因。根据对区域性流行临床病原体的 ARGs 调查，bla-like 和 bla-like 基因的检测是出乎意料的。与先前报道的环境基因相关的不同 bla 序列的发现支持了自然环境是耐药基因库的观点。在噬菌体中检测到的 ARGs 与在细菌群落中检测到的一样频繁，而且，在噬菌体部分中，bla 基因的多样性更高。噬菌体因此可能在环境中 ARGs 的传播中发挥作用，但它们也可能被用作监测循环 ARGs 的“报告基因”。
