摘要
目的了解不同来源金黄色葡萄球菌(简称金葡菌)的全基因组序列基本特征,探究菌株的分子分型、耐药基因型、毒力及其遗传进化关系。方法应用solexa高通量测序技术对10株医源性和食源性代表株金葡菌进行全基因组测序,以此进行多位点序列分型(multilocus sequence typing,MLST)、金葡菌a蛋白(Staphylococcus aureus protein A,spa)基因分型分析,并比较分析不同菌株基因组中携带耐药基因和毒力因子,筛选核心基因,构建系统进化树。结果10株金葡菌染色体基因组大小相似,均为2.7Mbp,包含有2486~2648个基因不等,平均长度约为887bp。耐药基因注释分析显示9株甲氧西林敏感金葡菌(MSSA)携带的耐药基因少于另一株耐甲氧西林金葡菌(MRSA)。尽管在不同菌株基因组之间的毒力因子数量无显著区别,但不同菌株存在的毒力因子却不同,食品来源金葡菌基因组携带1~4种数量不等的肠毒素基因。进化树分析显示不同来源金葡菌位于不同进化分支,2株为ST8型的MSSA和MRSA进化亲缘性较高,属于同一进化分支内。结论获得10株不同来源金葡菌的全基因组序列数据,并证实食源性或医院来源金葡菌为了适应不同生存环境,通过不同分子进化机制,获得不同耐药基因和毒力因子,形成菌株特定的分子遗传特征,可为金葡菌的分子流行病学和致病性机制研究提供参考依据。
Objective To understand the characteristics of whole-genomic sequence of Staphylococcus aureus from different sources,and to explore the molecular typing,drug resistance genotype,virulence and genetic evolution of those strains.Methods Solexa high-throughput sequencing technology was used to analyze the whole-genome of 10hospitalderived and food-borne representative S.aureus strains.Based on these results,multilocus sequence typing(MLST)and S.aureus A protein genotyping were determined,and comparative analysis were performed for drug resistance genes and virulence factors from different strain genomes.A phylogenetic tree was constructed by screening core genes from different genomes.Results The results showed that the chromosomal genomes of 10 S.aureus were similar in size,all of which were approximate 2.7Mbp,containing 2,486-2,648genes,and the average length was about 887bp.The drug resistance gene annotation analysis showed that 9methicillin-sensitive S.aureus(MSSA)carried less drug resistance genes than that of methicillin-resistant S.aureus(MRSA).Although there were no obvious differences in the number of virulence factors between the genomes of different strains,the virulence factors of different strains were distinct.It was found that the S.aureus genome from food sources carried 1-4types of enterotoxin genes.The phylogenetic tree showed that S.aureus from different sources were located in different phylogenetic branches,and the two ST8-type MSSA and MRSA have higher evolutionary relationship and belonged to the same phylogeny.Conclusion The whole-genome sequence data of 10 S.aureus strains from different sources were obtained.It was suggested that food-borne or hospital-derived S.aureus can adapt to different living environments through different molecular evolution mechanisms to obtain different drug resistance gene and virulence factors,which formed the specific molecular genetic characteristics of S.aureus strains.These results will provide a reference for subsequent studies on the molecular epidemiology and pathogenic mechanism of S.aureus.
作者
陈驰
石继春
王春娥
梁丽
龙新星
叶强
徐颖华
CHEN Chi;SHI Ji-chun;WANG Chun-e;LIANG Li;LONG Xin-xing;YE Qiang;XU Ying-hua(NHC Key Laboratory for Research on Quality and Standardization of Biotech Products,National Institute for Food and Drug Control,Beijing102629,China)
出处
《中国病原生物学杂志》
CSCD
北大核心
2022年第2期165-169,共5页
Journal of Pathogen Biology
基金
国家重点研发计划项目(No.2018YFC1603900)
国家科技基础条件平台-国家菌种资源库(No.NMRC-2021-2)。
关键词
金黄色葡萄球菌
不同来源
全基因组测序
毒力因子
耐药基因
Staphylococcus aureus
different sources
whole genome sequencing
virulence factor
drug resistance gene
