Epidemiology and genetic characterization of tet(X4)-positive Klebsiella pneumoniae and Klebsiella quasipneumoniae isolated from raw meat in Chengdu City, China  

作　　者：Weishuai Zhai Yiqing Wang Honghu Sun Bo Fu Qidi Zhang Congming Wu Jianzhong Shen Dejun Liu Yang Wang 

机构地区：[1]National Key Laboratory of Veterinary Public Health and Safety,College of Veterinary Medicine,China Agricultural University,Beijing 100193,China [2]Technology Innovation Center for Food Safety Surveillance and Detection,Sanya Institute,China [3]Agricultural University,Sanya 572025,China Irradiation Preservation Key Laboratory of Sichuan Province,Chengdu Institute of Food Inspection,Chengdu 611135,China [4]Collge of Veterlnary Medicine,Qingdao Agricultural University,Qingdao 266109,China

出　　处：《Biosafety and Health》2024年第2期116-124,共9页生物安全与健康（英文）

基　　金：supported by the National Key Research and Development Program of China(No.2022YFD1800400);National Natural Science Foundation of China(No.81991531);Natural Science Foundation of Shandong Province(No.ZR2020MC188);The sequence data of 25 K.pneumoniae isolates have been submitted to NCBI under BioProject accession number PRJNA1011004.

摘　　要：The rapid spread of mobile tigecycline resistance presents a significant public health threat,particularly with the increasing prevalence of tet(X4)-positive Enterobacterales across various species.This study aimed to inves-tigate the epidemic features and transmission dynamics of tet(X4)-positive Klebsiella pneumoniae(K.pneumo-niae)through the analysis of 206 raw meats,including pork(n=182),beef(n=16),duck(n=5),and chicken(n=3).These samples were collected from schools,markets,and restaurants in Chengdu City,China.A total of 25 isolates were obtained from 13 administrative regions.All isolates exhibited resistance to tetracycline,tigecycline,ampicillin,chloramphenicol,and florfenicol.Over half of the isolates also demon-strated resistance to streptomycin(80%),sulfamethoxazole/trimethoprim(72%),ciprofloxacin(64%),and ampicillin/sulbactam(56%).Among these strains,14 distinct sequence types(STs)were identified,revealing evidence of inter-regional clonal spread,notably among 9 K.pneumoniae ST3393.Phylogenetic analysis revealed the presence of two K.pneumoniae ST5 closely resembling hypervirulent K.pneumoniae from Jiangsu.Importantly,12 isolates were capable of transferring tigecycline resistance to Escherichia coli J53.Further plasmid analysis showed that the tet(X4)-harboring plasmids in K.pneumoniae could be classified into four types,primarily belonging to the IncFIA(HI1)/HI1A/HI1B hybrid plasmid(n=16)and IncFII plasmid(n=7),which significantly contributed to the cross-species dissemination of tet(X4).In summary,this study highlights the prevalence of MDR tet(X4)-positive K.pneumoniae in Chengdu,driven predominantly by clonal expansion and plasmid-mediated horizontal gene transfer.These findings emphasize the importance of contin-uous surveillance of tet(X4)-positive K.pneumoniae in raw meat and the implementation of effective measures to control their spread.

关 键 词：tet(X4) TIGECYCLINE K.pneumoniae Clonal spread Horizontal transfer 

分 类 号：R515[医药卫生—内科学] R181.3[医药卫生—临床医学]