海洋链霉菌Streptomyces sp.B-17卤化酶基因的克隆及生物信息学分析

海洋放线菌是生理活性物质重要的产生菌,而海洋放线菌产生的卤化酶可催化生理活性物质的卤化,极大提高了其抑菌和抗癌活性。从大连海域分离出1株链霉菌Streptomyces sp.B-17,从其基因组DNA中扩增一524 bp的基因片段,经与pMD-19T载体连接,转化大肠埃希菌JM109感受态细胞,重组质粒经鉴定证明正向插入到pMD-19T载体。生物信息学分析表明该序列与Actinocorallia herbida DSM 44252的2个依赖FADH2卤化酶基因的同源性为88%,拟编码氨基酸与色氨酸卤化酶(CP001848)的相似性也达到74%,证明所克隆的基因片段为卤化酶基因片段,为后续的基因功能分析及表达奠定了基础。

Cloning of A Halogenase Gene from Marine Streptomyces sp. B-17 and Its Bioinformatics Analysis

Marine actinomycetes（MA） are important sources of physiological active substances（PAS）,halogenase produced by the MA can catalyze the halogenization of the PAS,which greatly increased its antimicrobial and anticancer activities.A Streptomyces sp.B-17 strain was isolated from Dalian sea area,in this article a 524 bp gene fragment was amplified from its genomic DNA,after it was linked with pMD-19T vector and transferred into E.coli JM109 competence cell,the recombinant plasmid was identified and proved that it had been inserted in positive direction into pMD-19T vector.Bioinformatics analysis showed that the homology of the sequence of the cloned DNA fragment with two FADH2-dependent halogenase genes of Actinocorallia herbida DSM 44252 sequence was 88%,the similarity of the simulative encoded amino acid with tryptophan halogenase（CP001848） was also reached up to 74%,and it proved that the cloned gene fragment was halogenase gene fragment,and these had laid a foundation for the follow-up function analysis of the gene.