基于WGS的学生与环境MRSA菌株间毒素基因的相互关联分析  

Correlation of toxin genes between students and environmental MRSA strains based on WGS

作　　者：郭嘉佳 张文萃 贡梓军 梁月朗 程琦 姚振江 GUO Jia-jia;ZHANG Wen-cui;GONG Zi-jun;LIANG Yue-lang;CHENG Qi;YAO Zhen-jiang(Department of Epidemiology and Health Statistics,School of Public Health,Guangdong Pharmaceutical University,Guangzhou,Guangdong 510310,China)

机构地区：[1]广东药科大学公共卫生学院流行病与卫生统计学系,广东广州510310

出　　处：《现代预防医学》2023年第1期151-158,共8页Modern Preventive Medicine

基　　金：广东省科技计划项目(2014A020213013)。

摘　　要：目的探究学生鼻腔和学校环境耐甲氧西林金黄色葡萄球菌(methicillin-resistant staphylococcus aureus,MRSA)的毒素基因情况及遗传相似性。方法利用全基因组测序技术,比较广州市8所小学学生和环境中MRSA的毒素基因情况。采用χ^(2)检验或Fisher确切概率法分析毒素基因种类和数目的差异,构建系统进化树和聚类分析比较学生与环境的毒素基因谱。结果检出的135株MRSA中,学生与环境均携带以溶血毒素(hlgA、hlgB、hlgC)(96.88%~100.00%)和胞外酶基因(aur)(98.06%~100.00%)为主的毒素基因。在种类上,34种毒素基因除部分肠毒素基因(sec3、seg、sei、sem、sen、seo、seu)外,其余均无统计学差异(P>0.05);在携带基因数目上,除携带12种毒素基因在二者之间有差异(χ^(2)=12.35,P<0.001),其余均无差异(P>0.05)。此外,hlgA-hlgB-hlgC-aur-scn-sak和seg-sei-sem-sen-seo-seu为学生和环境MRSA的主要毒素基因谱,分别为(85.44%,81.25%)和(48.54%,71.88%)。不同分子型别MRSA与毒素基因模式之间存在关联(P<0.001)。结论学生与环境MRSA的毒素基因种类、数目相近,主要的毒素基因模式相同,种系进化树聚集,二者间存在较高的关联性,提示菌株在学生与环境中可能存在交叉传播现象。Objective To explore the toxin gene characteristics and genetic similarity of methicillin-resistant staphylococcus aureus(MRSA)in students’nasal cavity and school environment.Methods Using whole-genome sequencing technology,the toxin genes of MRSA in students and the environment in 8 primary schools in Guangzhou were compared.χ^(2)test or Fisher’s exact test was used to analyze the differences in species and number of toxin genes.Phylogenetic tree and cluster analysis were constructed to compare the toxin gene profiles of students and the environment.Results Among the 135 MRSA strains detected,both students and environment carried toxin genes dominated by hemolysis toxins(hlgA,hlgB,hlgC)(96.88%-100.00%)and extracellular enzyme genes(aur)(98.06%-100.00%).In terms of species,the 34 toxin genes were not statistically different except for some enterotoxin genes(sec3,seg,sei,sem,sen,seo,seu)(P>0.05).In terms of the number of genes carried,they were not different except for 12 toxin genes carried(χ^(2)=12.35,P<0.001)between them(P>0.05).In addition,hlgA-hlgB-hlgC-aur-scn-sak and seg-sei-sem-sen-seo-seu were the major toxin gene profiles of students and environmental MRSA with(85.44%,81.25%)and(48.54%,71.88%),respectively.There was an association between different molecular types of MRSA and toxin gene patterns(P<0.001).Conclusion The similarity in toxin gene types and numbers between students’and environmental MRSA,the same major toxin gene patterns,and the clustering of germline evolutionary trees indicate that there is a high correlation between the two,suggesting a possible cross-transmission of the strains in students and the environment.

关 键 词：MRSA 学生与环境 毒素基因 全基因组测序 

分 类 号：R372[医药卫生—病原生物学]