A组β-溶血性链球菌DNase B基因序列的克隆与序列分析

目的　克隆A组β -溶血性链球菌 (GroupAStreptococcus,GAS)DNaseB基因序列。 方法　根据genBank中登录的多种DNA酶B的序列 ,进行同源性分析 ,设计相对保守的针对DNaseB基因的引物 ,以链球菌基因组为模板进行PCR扩增 ,目的片段经TA克隆至pMD18-T质粒后测定其核酸序列 ,然后进行序列的查询与比对。结果　成功克隆出A组链球菌DNaseB基因全长序列共 810bp ,其中包括中 12 8bp的信号肽编码区和 6 81bp的成熟肽编码区 ,以及 5’端非编码区的一个T。结论　A组 β-溶血性链球菌DNaseB基因序列的成功克隆 ,为对其深入研究打下坚实基础

Cloning and sequence analysis of the DNase B gene of group A Streptococcus pyogenes

To construct a recombinant plasmid containing the DNase B group A Streptococcus pyogenes, a couple of more conserved primers was designed according to the sequences of DNase B gene published on the GenBank, and was amplified by PCR. The amplified DNase B gene from the genomic DNA of group A of Streptococcus pyogenes was then cloned into plasmid pMD18-T directly, and the cloned gene was sequenced.It was found that a group B gene of Streptococcus pyogenes with the full length of sequences of 810?bp is successfully cloned, and it comprises a signal peptide region of 128?bp, mature peptide region of 681?bp and a T in the un-coding region of 5' terminal end. These result would provide scientific basis for the further studies on the DNase B gene of group A Streptococcus pyogenes.