2型猪链球菌中国强毒株05ZYH33 sao基因敲除突变株的构建及其生物学功能

Construction and Characterization of sao Gene Knock-out Mutant of Streptococcus suis Serotype 2 Chinese Highly Virulent Strain 05ZYH33

摘要:

构建2型猪链球菌(Streptococcus suis serotype 2, S. suis 2)中国强毒株05ZYH33的sao基因敲除突变株。构建中间为壮观霉素抗性基因, 两侧为sao编码基因上下游同源序列的基因敲除载体, 同源重组筛选sao基因敲除突变株。PCR、RT-PCR、Western Blot对疑似突变株进行验证, 实验结果均证实sao基因完全被spc抗性基因替代, 成功构建了突变株05ZYH33Δsao。对野生型菌株和突变株进行菌落溶血活性、生长特性、小鼠致病性比较, 结果表明sao基因的敲除并未使野生型菌株在以上三方面产生明显的变化。筛选获得的05ZYH33 sao基因突变株为进一步研究sao基因在05ZYH33致病过程中的作用奠定了基础。

Abstract:

To construct the mutant strain Δsao, the recombinant gene knock-out vector was constructed consisting of Spcr cassette with the flanking homology regions of gene sao. The sao gene was replaced by Spcr cassette according to the principle of homologous recombination. PCR analysis, RT-PCR analysis and western blot were used to confirm that sao gene was replaced completely by the Spcr cassette. The results suggested that the mutant of 05ZYH33 sao gene was successfully constructed. Analysis of biological characteristics showed that there were no obvious distinctions in hemolytic activity, growth characteristics and virulence between the mutant and the wild type strain 05ZYH33. The construction of the mutant strain 05ZYH33Δsao laid the foundation for father research on the role of sao during infection.