Antimicrobial resistance characteristics and phylogenetic relationships of pleuromutilin-resistant Enterococcus isolates from different environmental samples along a laying hen production chain  

作　　者：Cong Lin Yuxuan Feng Xianjun Xie Haoyu Zhang Jie Wu Yixiao Zhu Jing Yu Jingyi Feng Wen Su Shanming Lai Anyun Zhang 

机构地区：[1]Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province,Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education,College of Life Sciences,Sichuan University,Chengdu 610065,China

出　　处：《Journal of Environmental Sciences》2024年第3期195-205,共11页环境科学学报（英文版）

基　　金：supported by the National Key Research and Development Program of China (Nos.2022YFC2303900 and2022YFD1800400);the General Program of National Natural Science Foundation of China (Nos.U21A20257 and 31830098);the National System of Layer Production Technology (No.CARS-40-K-14);the Key R&D Program of Sichuan Province (Nos.2022ZDZX0017 and 2021YFH0192)。

摘　　要：Antimicrobial resistance in the laying hen production industry has become a serious public health problem.The antimicrobial resistance and phylogenetic relationships of the common conditional pathogen Enterococcus along the laying hen production chain have not been systematically clarified.105 Enterococcus isolates were obtained from 115 environmental samples (air,dust,feces,fies,sewage,and soil) collected along the laying hen production chain (breeding chicken,chick,young chicken,and commercial laying hen).These Enterococcus isolates exhibited resistance to some clinically relevant antibiotics,such as tetracycline (92.4%),streptomycin (92.4%),and erythromycin (91.4%),and all strains had multidrug resistance phenotypes.Whole genome sequencing characterized 29 acquired antibiotic resistance genes (ARGs) that conferred resistance to 11 classes of antibiotics in 51pleuromutilin-resistant Enterococcus isolates,and lsa(E),which mediates resistance to pleuromutilins,always co-occurred with lnu(B).Alignments with the Mobile Genetic Elements database identified four transposons (Tn554,Tn558,Tn6261,and Tn6674) with several ARGs(erm(A),ant(9)-la,fex(A),and optrA) that mediated resistance to many clinically important antibiotics.Moreover,we identified two new transposons that carried ARGs in the Tn554 family designated as Tn7508 and Tn7492.A complementary approach based on conventional multi-locus sequence typing and whole genome single nucleotide polymorphism analysis showed that phylogenetically related pleuromutilin-resistant Enterococcus isolates were widely distributed in various environments on different production farms.Our results indicate that environmental contamination by antimicrobial-resistant Enterococcus requires greater attention,and they highlight the risk of pleuromutilin-resistant Enterococcus and ARGs disseminating along the laying hen production chain,thereby warranting effective disinfection.

关 键 词：Antimicrobial resistance ENTEROCOCCUS Laying hen production chain Pleuromutilin 

分 类 号：S858.31[农业科学—临床兽医学]