Agricultural use of antibiotics is recognized by the U.S. Centers for Disease Control and Prevention as a major contributor to antibiotic-resistant infections. While most One Health attention has been on the potential for antibiotic resistance transmission from livestock and contaminated meat products to people, plant foods are fundamental to the food chain for meat eaters and vegetarians alike. We hypothesized that environmental bacteria that colonize plant foods may serve as platforms for the persistence of antibiotic-resistant bacteria and for horizontal gene transfer of antibiotic-resistant genes. Donor Acinetobacter baylyi and recipient Escherichia coli were cocultured in vitro, in planta on lettuce, and in vivo in BALB/c mice. We showed that nonpathogenic, environmental A. baylyi is capable of transferring plasmids conferring antibiotic resistance to E. coli clinical isolates on lettuce leaf discs. Furthermore, transformant E. coli from the in planta assay could then colonize the mouse gut microbiome. The target antibiotic resistance plasmid was identified in mouse feces up to 5 days postinfection. We specifically identified in vivo transfer of the plasmid to resident Klebsiella pneumoniae in the mouse gut. Our findings highlight the potential for environmental bacteria exposed to antibiotics to transmit resistance genes to mammalian pathogens during ingestion of leafy greens.

中文翻译：

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生菜上抗生素耐药性从贝氏不动杆菌到大肠杆菌的水平基因转移以及随后抗生素耐药性向肠道微生物组的传播。


美国疾病控制和预防中心认为农业使用抗生素是导致抗生素耐药性感染的主要原因。虽然“One Health”的大多数关注点都集中在抗生素耐药性从牲畜和受污染的肉制品传播给人类的可能性上，但植物性食品对于肉食者和素食者的食物链至关重要。我们假设，在植物性食物中定殖的环境细菌可能作为抗生素抗性细菌持久存在和抗生素抗性基因水平基因转移的平台。供体贝氏不动杆菌和受体大肠杆菌在体外、生菜植物和 BALB/c 小鼠体内共培养。我们证明，非致病性环境A. baylyi能够将赋予生菜叶盘上的大肠杆菌临床分离株抗生素抗性的质粒转移。此外，来自植物体内测定的转化大肠杆菌可以在小鼠肠道微生物组中定殖。感染后 5 天，在小鼠粪便中鉴定出目标抗生素抗性质粒。我们特别鉴定了该质粒在体内转移至小鼠肠道中的肺炎克雷伯氏菌。我们的研究结果强调了暴露于抗生素的环境细菌在摄入绿叶蔬菜期间将抗性基因传递给哺乳动物病原体的潜力。