1株9型猪链球菌全基因组分析北大核心CSCD

目的探索9型猪链球菌基因组功能及遗传关系。方法采用生物信息学方法对1株9型猪链球菌强毒株GD18的全基因组序列进行注释,并与GenBank上的15株猪链球菌进行比较基因组学分析。结果GD18菌株基因组全长2067661 bp,总蛋白1961个,注释到COG、GO、KEGG、CAZy和PHl-base数据库的基因分别占总蛋白的77.05%、71.29%、43.91%、4.49%和3.37%。毒力因子分析表明猪链球菌毒力因子的复杂以及并非所有的猪链球菌菌株都有一套通用的毒力因子。耐药基因分析表明GD18含多种类的耐药基因,且存在丰富的外排系统。蛋白预测结果显示GD18具有114个信号肽蛋白和30个分泌蛋白。16个菌株基因组比较分析发现共有的核心基因为1244个,非共有基因共1685个,特有基因共1417个。进化分析表明GD18与加拿大分离株89-3576-3亲缘关系最近,且国内菌株基本处在不同分支。结论对1株9型猪链球菌分离株的全基因组、基因功能、进化关系等进行分析,为9型猪链球菌基因组整体水平的研究奠定基础和提供数据支撑。

Genomic analysis of a strain of Streptococcus suis serotype 9

In this study, the whole genome sequence of the virulent strain of Streptococcus suis serotype 9 GD18 was annotated through bioinformatics methods, and comparative genomics analysis was performed with 15 strains of S. suis in GenBank. The genome of GD18 is 2 067 661 bp, with 1 961 proteins. The genes annotated in COG, GO, KEGG, CAZy and PHL-Base accounted for 77.05%, 71.29%, 43.91%, 4.49% and 3.37% of GD18 total protein, respectively. Virulence factor analysis indicated that the virulence factors of S. suis were complex, and not all S. suis strains shared a set of common virulence factors. Drug resistance gene analysis revealed that GD18 contains many drug resistance genes and has a rich drug efflux system. GD18 contains 114 signal peptide proteins and 30 secretory proteins. A total of 1 244 core genes, 1 685 dispensable genes and 1 417 specific genes were identified in 16 S. suis strains through comparative genome analysis. Phylogenetic analysis indicated that GD18 was most closely related to the Canadian strain 89-3576-3, and the domestic strains were located in different branches. Therefore, the genetic relationships among S. suis strains are complex, and their evolutionary pathway is diverse in China. This study lays a foundation and provides data support for research on the overall level of the genome of S. suis serotype 9.