blaNDM-1基因敲除对阴沟肠杆菌毒力的影响  

Effect of blaNDM-1 gene knockout on virulence of Enterobacter cloacae

作　　者：代鹏飞[1] 杨恺 杜艳[1] 刘淑敏[1] DAI Pengfei;YANG Kai;DU Yan;LIU Shumin(Department of Clinical Laboratory,First Affiliated Hospital,Kunming Medical University,Yunnan Key Laboratory of Laboratory Medicine,Yunnan Provincal Clinical Research Center for Laboratory Medicine,Kunming 650032,China)

机构地区：[1]昆明医科大学第一附属医院医学检验科云南省检验医学重点实验室云南省医学检验临床医学研究中心,云南昆明650032

出　　处：《吉林大学学报（医学版）》2022年第6期1389-1394,共6页Journal of Jilin University：Medicine Edition

基　　金：国家自然科学基金项目(81960382);云南省科技厅应用基础研究计划联合专项(2019FE001-060,202101AY070001-107)。

摘　　要：目的:比较bla NDM-1基因敲除前后阴沟肠杆菌毒力的变化,阐明bla NDM-1基因对其毒力的影响。方法:将携带bla NDM-1基因的阴沟肠杆菌分为携带耐药基因bla NDM-1的阴沟肠杆菌T2(T2组)、阴沟肠杆菌T2 bla NDM-1基因敲除株(ΔT2组)和阴沟肠杆菌ATCC13047 (ST组)。检测各组质粒稳定性、各组阴沟肠杆菌的菌落运动直径、生物膜吸光度(A)值、黏附细菌量、黏附率及侵袭黏附比。结果:传代200次后,T2组阴沟肠杆菌仍携带bla NDM-1基因,ΔT2和ATCC13047组阴沟肠杆菌不携带bla NDM-1基因;T2组阴沟肠杆菌仅携带碳青霉烯类耐药基因bla NDM-1,其他碳青霉烯类耐药基因bla KPC-2、bla IMP-4、bla VIM-1和bla OXA-48均为阴性;ΔT2和ST组所检测的5种碳青霉烯类耐药基因均为阴性,T2与ΔT2组阴沟肠杆菌携带相同的毒力基因clp B、icmf和acr A。T2组菌落运动直径小于ΔT2和ST组(P<0.05)。与T2组比较,ΔT2组生物膜A值升高,但差异无统计学意义(P>0.05)。与T2组比较,ΔT2组黏附细菌量降低,但差异无统计学意义(P>0.05)。共培养24 h后,T2组和ΔT2组RAW264.7细胞的黏附率和侵袭黏附比低于ST组(P<0.05)。结论:bla NDM-1基因未明显增加阴沟肠杆菌的毒力。Objective:To compare the changes of virulence of Enterobacter cloacae before and after blaNDM-1 gene knockout,and to clarify the effect of blaNDM-1 gene on the virulence of Enterobacter cloacae. Methods:The Enterobacter cloacae carrying blaNDM-1 gene were divided into Enterobacter cloacae T2 carrying drug resistant gene blaNDM-1 group(T2 group),Enterobacter cloacae T2 with blaNDM-1 gene-knockout group(ΔT2 group)and Enterobacter cloacae ATCC13047 control group(ST group). The stabilities of the plasmids in various groups were detected,and the colony movement diameters,biofilm absorbance(A)values,amounts of adhesion bacteria,adhesion rates and invasion adhesion ratios of the Enterobacter cloacae in various groups were detected. Results:After 200 passages,the Enterobacter cloacae in T2 group still carried blaNDM-1 gene,while the Enterobacter cloacae in Δ T2and ATCC13047 groups did not carry blaNDM-1 gene;the Enterobacter cloacae in T2 group only carried the carbapenem resistance gene blaNDM-1,while the other carbapenem resistance genes blaKPC-2,blaIMP-4,blaVIM-1 and blaOXA-48 were negative;five carbapenem resistance genes detected in Δ T2and ST groups were negative;the Enterobacter cloacae in T2 and Δ T2 groups carried the same virulence genes clpB,icmf and acrA. The colony movement diameter of the bacteria in T2 group was smaller than those in Δ T2 and ST groups(P<0. 05). Compared with T2 group,the biofilm A value in Δ T2 group was increased,but the difference was not significant(P>0. 05). Compared with T2 group,the amount of adhesion bacteria in Δ T2 group was decreased,but the difference was not significant(P>0. 05). After coculture for 24 h,the adhesion rate and invasion adhesion ratio of the RAW264. 7 cells in T2 group and Δ T2group were lower than that in ST group(P<0. 05). Conclusion:BlaNDM-1 does not significantly increase the virulence of Enterobacter cloacae.

关 键 词：阴沟肠杆菌 blaNDM-1 基因敲除 毒力 耐药 

分 类 号：R378.2[医药卫生—病原生物学]