Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou Universitygrid.268415.c, Yangzhou, China.
Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou Universitygrid.268415.c, Yangzhou, China.
Microbiol Spectr. 2021 Oct 31;9(2):e0041621. doi: 10.1128/Spectrum.00416-21. Epub 2021 Sep 15.
We isolated eight tigecycline-resistant strains from a pig farm in Shanghai, China, including Escherichia coli ( = 1), Proteus cibarius ( = 1), and Enterobacter hormaechei ( = 6). Two of them (E. coli and P. cibarius) were positive for (X). E. coli SH19PTE6 contained an IncFIA18/IncFIB(K)/IncX1 hybrid plasmid pYUSHP6-tetX, highly similar to other (X)-bearing hybrid plasmids from E. coli in China. In P. cibarius SH19PTE4, (X) was located within a new chromosomal integrative and conjugative element (ICE), ICEChn2, belonging to the SXT/R391 ICE family. All tigecycline-resistant E. hormaechei isolates carried the (A) variant; cloning and transfer of this (A) variant into various hosts increased their MICs for tigecycline (4- to 8-fold). Tigecycline resistance observed on a pig farm is mediated by the (A) variant and (X) via a plasmid or ICE. The rational use of antibiotics such as doxycycline and surveillance of tigecycline resistance in livestock are warranted. As a last-resort antimicrobial agent to treat serious infections, the emergence and spread of tigecycline resistance in and Acinetobacter have raised global concerns. Multiple mechanisms mediate tigecycline resistance in , such as the monooxygenase Tet(X), mutations in Tet proteins, and overexpression of efflux pumps. Although tigecycline is not approved for animals, tigecycline resistance has been observed in Escherichia coli, Proteus cibarius, and Enterobacter hormaechei isolates on a pig farm, mediated by the (A) variant and (X) via a plasmid or ICE. The heavy use of tetracyclines such as doxycycline in food-producing animals in China may be the reason for the emergence and transmission of tigecycline resistance.
我们从中国上海的一个养猪场中分离出了 8 株替加环素耐药菌株，包括大肠杆菌（=1）、奇异变形杆菌（=1）和蜂房哈夫尼菌（=6）。其中 2 株（大肠杆菌和奇异变形杆菌）为（X）阳性。大肠杆菌 SH19PTE6 含有一个 IncFIA18/IncFIB(K)/IncX1 杂合质粒 pYUSHP6-tetX，与中国其他大肠杆菌携带（X）的杂合质粒高度相似。在奇异变形杆菌 SH19PTE4 中，（X）位于一个新的染色体整合和共轭元件（ICE）ICEChn2 内，属于 SXT/R391 ICE 家族。所有替加环素耐药蜂房哈夫尼菌分离株均携带（A）变体；将此（A）变体克隆并转移到各种宿主中，增加了它们对替加环素的 MIC（4-8 倍）。养猪场中观察到的替加环素耐药性是由（A）变体和（X）通过质粒或 ICE 介导的。需要合理使用抗生素（如强力霉素）并监测畜牧业中的替加环素耐药性。作为治疗严重感染的最后手段的抗菌药物，替加环素在和不动杆菌中的耐药性的出现和传播引起了全球关注。多种机制介导了中的替加环素耐药性，如单加氧酶 Tet(X)、Tet 蛋白的突变和外排泵的过度表达。尽管替加环素未被批准用于动物，但在养猪场的大肠杆菌、奇异变形杆菌和蜂房哈夫尼菌分离株中已经观察到了替加环素耐药性，由（A）变体和（X）通过质粒或 ICE 介导。在中国，四环素类药物（如强力霉素）在食用动物中的大量使用可能是替加环素耐药性出现和传播的原因。
