一个融合魏斯氏菌隐蔽质粒的序列分析

Complete DNA Sequence Analysis of a Cryptic Plasmid Isolated from Weissella confusa

从融合魏斯氏菌(Weissella confusa QJ012)中发现一个隐蔽质粒(p QJ012),测序结果显示该质粒大小为1489 bp,碱基G+C含量为42.8%。BLAST结果显示该质粒的核苷酸序列同pJY33和pKLCA的同源性分别为93%、92%。ORF1编码一个282个氨基酸残基的复制蛋白(Rep),其氨基酸序列与质粒pJY33和pKLCA的同源性分别为91%、85%。根据复制蛋白、dso和sso的序列特征,推定pQJ012的复制方式为滚环复制,是滚环复制pT181家族成员。质粒pQJ012可能构建为良好的表达载体。

A cryptic plasmid isolated from Weissella confusa QJ012, designated as pQJ012, was sequenced and characterized, and it was a 1489 bp circular molecule with a 42.8% G＋C content. The result of BLAST showed that nucleotide sequence of pQJ012 was in homology with pJY33 （ 93% ） and pKLCA （ 92% ） . ORF1 encoded a 282 amino acid residue Rep protein that was 91% identical to pJY33 and 85% identical to pKLCA in homology. Sequence analysis indicated that plasmid pQJ012 belonged to pT181 family of rolling-circle replication（ RCR ）. The pQJ012 may be constructed as a promising expression vector.