一种纳豆芽孢杆菌的分子鉴定及纳豆激酶基因克隆

摘要

LJQ-NK, a strain with ability of fibrinolysis was identified by molecular biology method. Sequence analysis shows that the homology of 16S rRNA between LJQ-NK and Bacillus subtilis natto was exceeded 99. 9%. The putative nattokinase cDNA was cloned from LJQ-NK using RT-PCR and a 1 126 bp cDNAclone was obtained. Result of BLAST-X sequence homology search show that two bases of putative nattokinase cDNA clone were differed from nattokinase and the ORF sequence of nattokinase between LJQ-NK and Bacillus subtilis natto were identical.%　　以实验室保藏的一株具有溶解血栓能力的芽孢杆菌(LJQ-NK)为出发菌株，通过形态学分析和16SrRNA 比对，对菌株进行鉴定，更进一步利用聚合酶链式反应(PCR)克隆纳豆激酶 DNA 片段⑤16SrRNA比对.结果表明LJQ-NK与已报道的纳豆激酶16SrRNA序列有99.9%以上的同源性，初步认定为一株纳豆芽孢杆菌.克隆获得1120 bp的DNA片段，应用DNAMAN软件分析，与已报道的纳豆激酶编码基因(GI29164926)存在两个碱基的差异，编码纳豆激酶开放阅读框区域序列完全相同.