Genetic evolution,drug resistance,and biofilm formation capacity of E.coli O157:H7 from different animal sources in Xinjiang
10.16303/j.cnki.1005-4545.2025.04.09
- VernacularTitle:新疆地区不同动物源E.coli O157:H7遗传进化分析及耐药性与成膜能力研究
- Author:
Yan WANG
1
;
Ling ZHANG
1
;
Yifan LIU
1
;
Wanpeng MA
1
;
Tian QIN
1
;
Wei WANG
1
;
Zhanqiang SU
1
Author Information
1. 新疆农业大学动物医学学院,新疆乌鲁木齐 830000
- Publication Type:Journal Article
- Keywords:
E.coli O157:H7;
cluster;
MLST;
drug resistance;
plasmid replicon;
integron
- From:
Chinese Journal of Veterinary Science
2025;45(4):685-692
- CountryChina
- Language:Chinese
-
Abstract:
Different animals in Xinjiang carry Escherichia coli O157:H7(E.coli O157:H7),but the connection between these strains is not clear.This study aims to understand the evolutionary sub-group of E.coli O157:H7,the distribution of the dominant genetic lineage,the biofilm formation ability,the carriage of mobile genetic elements and their drug resistance profile.E.coli O157:H7 was identified by PCR.Multilocus sequence typing(MLST)protocol was used for E.coli O157 to detect ST type,plasmid replicon and integron genes.Biofilm formation ability was determined by crystal violet microplate,and Kirby-Bauer was used to detect drug resistance.The results showed that 46.7%(7/15)of E.coli O157:H7 belongs to Group A,53.3%(8/15)of E.coli O157:H7 be-longs to Group E.Sheep source were mainly prevalent in Group A(4/6).Cattle sources are mainly Group E(6/7).A total of six ST types were detected:ST11(8/15),ST-206(1/15),ST-6126(3/15),ST-1640(1/15),ST-178(1/15),ST-4550(1/15).Two strains had a moderate biofilm-form-ing capacity,two strains had a weak biofilm-forming capacity,10 strains have no biofilm-forming capacity.All were multidrug-resistant strains,with complete resistance to lincomycin,oxacillin,clindamycin,vancomycin,midemycin and cefthiophene,and 88%-94%resistance to poly-myxin B,ampicillin,penicillin G and erythromycin,they are highly drug resistant.The five resist-ance genes detected were acrA(66.66%,10/15),tolC(73.33%,11/15),qurS(13.33%,2/15),floR and qurA(6.67%,1/15).Four plasm id replicons were detected,they were IncP(66.66%,10/15),IncFrepB(86.67%,13/15),IncFIA(6.67%,1/15),IncFIB(66.66%,10/15).Two class Ⅰ integrons were detected and they were ISCR1(33.33%,5/15),ISECP1(20%,3/15).The re-sults showed that E.coli O157:H7 in Xinjiang was predominantly prevalent in Group A and Group E.Sheep sources were predominantly prevalent in Group A,and cattle sources were predominantly prevalent in Group E.The ST types were widely distributed,with ST11 types being the predomi-nant type,the biofilm-forming ability was weak,and the resistance was strong,all of them were multi-drug-resistant strains,and the resistance genes were mainly externally excreted from the pumps,and the resistance genes had more spreading elements.