地芽孢杆菌属DYth03 DNA聚合酶基因的克隆、表达及性质分析  

Cloning,expression and characterization of the DNA polymerase gene from Geobacillus sp.DYth03

作　　者：罗淑娅[1] 李侃[1] 徐丽美[1] 

机构地区：[1]国家海洋局第三海洋研究所国家海洋局海洋生物遗传资源重点实验室,福建厦门361005

出　　处：《台湾海峡》2011年第1期17-20,共4页Journal of Oceanography In Taiwan Strait

基　　金：国家863计划资助项目(2007AA091407)

摘　　要：从东太平洋热液区E53站位的深海沉积物样品中分离出1株能在65℃生长的嗜热菌(DYth03).该菌的16S rDNA序列与地芽孢杆菌属(Geobacillus)内各种之间的同源性为98%以上.克隆得到DYth03的DNA聚合酶基因(DYth-pol),序列分析表明该基因全长为2 631 bp,G+C含量为55.5%,推测编码为876个氨基酸,与BstDNApolI的同源性最高(达98%).将该聚合酶基因克隆到pTTQ-h表达载体上,并在大肠杆菌DH1中进行表达.对纯化到的表达产物进行酶活性测定,结果表明该酶具有聚合酶活性和5’-3’外切酶活性.A strain of thermophilic bacteria（DYth03） that can grow at 65℃ was isolated from the sediment of a hydrothermal vent field on the E53 site of the east Pacific Ocean.The 16S rDNA of DYth03 shared more than 98% sequence homology with related Geobacillus species.The gene encoding the DNA polymerase of DYth03（DYth-pol） was cloned and sequenced.Analysis indicated that the gene was 2 631 bp in length with a G＋C content of 55.5%,encoding an 876-amino-acid peptide,which was most similar to that of Bst DNApolI（98%）.The DYth-pol gene was cloned in the expression vetor pTTQ-h and expressed in E.coli DH1.The expressed product was purified and characterized.It showed 5＇-3＇ exonuclease and polymerase activity.

关 键 词：海洋生物学 嗜热菌 地芽孢杆菌属(Geobacillus) 16S rDNA 耐热DNA聚合酶 基因表达 东太平洋 

分 类 号：Q7[生物学—分子生物学]