摘要
目的通过比较猪链球菌2型强毒株与弱毒株和无毒株的基因组差异,发现新的基因岛,探讨猪链球菌的基因群水平转移及其与致病性之间的关系。方法在已知猪链球菌2型强毒株全基因组序列和对可能基因岛的分析基础上,通过DNA测序和生物信息学分析,对基因岛的结构进行分析鉴定,并预测其功能。结果发现了一个只存在于猪链球菌2型中国强毒株,而在弱毒株和无毒株中整体缺失的新基因岛,命名为SSGI4。基因岛全长11 269bp,G+C含量(36.8%)明显低于基因组总G+C含量(41.1%),基因岛两端均有10bp的正向重复序列,并且末端携带有噬菌体整合酶基因,显示很可能是通过溶原性噬菌体整合入基因组。基因岛包含11个编码基因,部分基因推测为可能的膜表面蛋白基因或氨基酸结合蛋白基因。结论新发现的基因岛SSGI4具有致病性基因岛的各项典型特征,可能与猪链球菌2型强毒株的致病性有关,具有深入研究的价值。
A novel genomic island （GI） in Streptococcus suis serotype 2（SS2） was identified, which resided in the highly virulent strains but not in the hypo-virulent strains or avirulent strains of SS2 of the Chinese isolates. This newly discovered GI strain was designated as SSGI4 and its whole length of genome was 11 269 bps, sharing the typical properties of pathogenicity islands, such as the distinct G＋C content, a mosaic architecture characteristics and the specificity for virulent isolates. There were 11 genes within SSGI4, in which some genes were putative cell surface protein genes and others were amino acid-binding protein genes. Our finding sheds light on the investigation of horizontal gene transfer in SS2 and their influence on pathogenicity.
出处
《中国人兽共患病学报》
CAS
CSCD
北大核心
2009年第7期615-618,共4页
Chinese Journal of Zoonoses
基金
国家973项目(2006CB504402)
吉林省科技发展计划资助项目(No.20080130)
关键词
猪链球菌2型
基因岛
SSGI4
Streptococcus suis serotype 2
genomic island SSGI4
