摘要

       猪粪便是一种严重的环境污染物。抗生素抗性基因 (ARG) 和毒力相关基因 (VAG) 的携带以及来自猪的共生大肠杆菌的人畜共患病潜力在很大程度上是未知的。此外，关于共生大肠杆菌作为促进食用动物和环境之间 ARG 动员的贡献者的作用知之甚少。在这里，我们报告了来自澳大利亚新南威尔士州两个商业生产设施的健康猪粪便的 103 种 1 类整合子阳性大肠杆菌的全基因组序列分析。大多数菌株属于系统群 A 和 B1，并携带与人类肠外感染有关的 VAG。 103个菌株属于37个多位点序列类型，克隆复合体10个突出。检测到 17 个 ARG，97 % (100/103) 的菌株携带三个或更多 ARG。重金属抗性基因 merA、cusA 和 terA 也很常见。 IS26 在 98% (101/103) 的菌株中观察到，并且通常与结构多样的 1 类整合子在物理上相关，这些整合子具有独特的遗传特征，可以跟踪。据我们所知，这项研究为澳大利亚猪源共生大肠杆菌提供了第一个详细的基因组分析和参考点，有助于追踪特定谱系及其携带的移动抗性基因。

       Pig manure is a serious environmental pollutant. The carrying of antibiotic resistance genes (ARG) and virulence-associated genes (VAG) and the zoonotic potential of commensal E. coli from pigs are largely unknown. In addition, little is known about the role of symbiotic E. coli as a contributor to ARG mobilization between food animals and the environment. Here, we report the whole genome sequence analysis of 103 Type 1 integron-positive E. coli from healthy pig feces from two commercial production facilities in New South Wales, Australia. Most strains belong to system groups A and B1 and carry VAG related to human extraintestinal infections. 103 strains belong to 37 multi-site sequence types, and 10 clone complexes are prominent. Seventeen ARGs were detected, and 97% (100/103) of the strains carried three or more ARGs. The heavy metal resistance genes merA, cusA and terA are also common. IS26 is observed in 98% (101/103) of strains and is usually physically related to the structurally diverse type 1 integrons. These integrons have unique genetic characteristics and can be tracked. As far as we know, this study provides the first detailed genome analysis and reference point for Australian pig-derived symbiotic E. coli, which helps to track specific pedigrees and the mobility resistance genes they carry.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5761274/