摘要
新疆不同动物都携带大肠杆菌O157:H7(E.coliO157:H7),但是这些菌株之间的联系不清楚。为了解E.coli O157:H7的进化分群、优势遗传谱系的分布、生物膜形成能力、携带可移动遗传元件情况及其耐药谱,对E.coli O157:H7用多重PCR法鉴定系统进化分群,通过多位点序列分型(multilocussequencetyping,MLST)方案检测E.coliO157ST型,结晶紫微孔板法测定生物被膜形成能力(BF),Kirby-Bauer法检测耐药情况,PCR法检测耐药、质粒复制子、整合子基因。结果显示新疆46.7%(7/15)的E.coliO157:H7属于A群,53.3%(8/15)属于E群,羊源以A群流行为主(4/6),牛源以E群为主(6/7);共检测出6种ST型,分别为ST11(8/15)、ST-206(1/15)、ST-6126(3/15)、ST-1640(1/15)、ST-178(1/15)、ST-4550(1/15);有2株具有中等成膜能力,2株具有弱成膜能力,10株无成膜能力;均为多重耐药菌株,对林可霉素、苯唑西林、克林霉素、万古霉素、麦迪霉素和头孢噻吩完全耐药,多黏菌素B、氨苄西林、青霉素G、红霉素耐药率为88%~94%,具有高度耐药性;检测到5种耐药基因,分别是acrA(66.66%,10/15)、tolC(73.33%,11/15)、qurS(13.33%,2/15)、floR和qurA(6.67%,1/15);4种质粒复制子,分别是IncP(66.66%,10/15)、IncFrepB(86.67%,13/15)、IncFIA(6.67%,1/15)、IncFIB(66.66%,10/15);2种Ⅰ类整合子,分别是ISCR1(33.33%,5/15)、ISECP1(20%,3/15)。结果显示,新疆地区的E.coliO157:H7以A群和E群流行为主,羊源以A群流行为主,牛源以E群为主,ST型分布较广,其中以ST11型为主,生物膜成膜能力较弱,耐药性强,均为多重耐药菌株,耐药基因以外排泵为主,耐药基因传播元件较多。
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 subgroup 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 belongs 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-forming capacity,two strains had a weak biofilm-forming capacity,lo strains have no biofilm-forming capacity.All were multidrug-resistanst trains,withcomplete resistancet to lincomycin,oxacillin,clindamycin,vancomycin,midemycin and cefthiophene,and 88%-94%resistance to polymyxin B,ampicillin,penicillin G and erythromycin,they are highly drug resistant.The five resistance 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 plasmid 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 Iintegrons were detected and they were ISCR1(33.33%,5/15),ISECP1(20%,3/15).The results 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 STll types being the predominant 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.
作者
王燕
张凌
刘怡帆
马万鹏
秦天
王伟
苏战强
WANG Yan;ZHANG Ling;LIU Yifan;MA Wanpeng;QIN Tian;WANG Wei;SU Zhanqiang(college of Veterinary Medicine,Xinjiang Agricultural University,Urumqi 830000,China)
出处
《中国兽医学报》
北大核心
2025年第4期685-692,共8页
Chinese Journal of Veterinary Science
基金
新疆自治区重点研发资助项目(2023A02007-3)
自治区“三农”骨干人才培养资助项目(2023SNGGNT005)
新疆自治区重点研发资助项目(2023B02039-3)。
