嗜热菌EPT3硫酸酯酶基因的克隆及生物信息学分析

利用筛选培养基筛选到一株产硫酸酯酶的深海嗜热菌EPT3，通过16SrDNA分析，将该菌株归属为Geobacillussp．EPT3．以菌株EP＇13的基因组DNA为模板，使用硫酸酯酶引物进行PCR扩增，将目的基因克隆至pUCm—T载体后进行测序．测序结果表明，克隆基因的大小为1956bp，预测编码651个氨基酸残基．对该基因编码蛋白质进行了生物信息学分析，结果表明，该蛋白质序列与其他菌株来源的硫酸酯酶具有很高的相似性，提示本研究克隆的基因编码硫酸酯酶．该硫酸酯酶的理论分子质量为75．1ku，理论等电点为6．90．采用同源建模法建立了GeobaciUussp．EPT3硫酸酯酶的三维结构模型，为球状结构．

Cloning and Bioinformatics Analysis of the Sulfatase Gene from Thermophilic Geobacillus sp.EPT3

A deep-sea therrnophilic strain EPT3 producing sulfatase was obtained by selective medium. On the basis of I6S rDNA sequence alignment, the strain was assigned to Geobacillus sp. EPT3. With the ge- nomic DNA of strain EPT3 as a template, the sulfatase gene was amplified using a pair of primers. The target gene was cloned into pUCm-T vector and then sequenced. DNA sequence showed that the cloned gene was 1956 bp in length, encoding 651 amino acid residues. This protein sequence was further analyzed by bioinformatics, and the results revealed that the target sequence shared high identities with the sulfatase sequences from other bacteria. The cloned gene was thus predicted to be a sulfatase. The theoretical molecular weight and pI of this sulfatase were 75.1 ku and 6.90, respectively. Based on homology modeling, the three-dimensional structure of Geobacillus so. EPT3 sulfatase presented as a globular structure.