酸土脂环酸芽孢杆菌具有嗜酸耐热的独特生理特性，从该属细菌中分离到的多种酶类都具有耐酸热稳定性，是筛选耐酸耐热酶的重要菌种资源。超氧化物歧化酶(SOD)由于具有重要的生理功能而广泛用于食品、药品及化妆品等行业。为了深入探讨酸土脂环酸芽孢杆菌SOD的分子生物学特性，本研究利用同源克隆、交错式热不对称PCR技术和生物信息学方法进行Fe-SOD基因克隆、测序及序列分析。结果表明，Fe-SOD基因（GenBank序列号：JN614998）ORF全长为606 bp，编码202个氨基酸，其推测氨基酸序列与来源于酸热脂环酸芽孢杆菌DSM 446的Fe-SOD（ACV58017.1）序列相似性最高，为78%。整个蛋白序列含有Fe/MnSODs家族的5个模体，SOD活性中心含有金属离子结合配基His27、His82、Asp164和His168，具有Fe/MnSODs家族典型的蛋白结构特征。酸土脂环酸芽孢杆菌Fe-SOD基因的克隆和生物信息学分析为进一步构建原核表达载体、获得生产耐酸热Fe-SOD的基因工程菌株奠定基础。

Alicyclobacillus acidoterrestris, a genus of acidophilic and thermophilic resistant bacteria, is an important microbial resource of heat and acid resistant enzymes, a variety of enzymes isolated from which have acid and thermal stability. Superoxide dismutase (SOD) is widely used in food, clinical treatment, and cosmetic industry for its important physiological functions. In order to deeply explore the molecular properties of SOD gene in Alicyclobacillus acidoterrestris, the Fe-SOD gene was cloned, sequenced and analysed using homologous cloning, thermal asymmetric interlaced PCR and bioinformatics. The results showed that Fe-SOD gene(GenBank accession number: JN614998) contains a complete ORF of 606 bp, encoding 202 amino acid, the deduced amino acid sequence shared the highest homology with Fe-SOD from A. acidocaldarius DSM 446 (78%). A. acidoterrestris Fe-SOD is composed of five motifs and the active site of SOD contains the residues of His27, His82, Asp164, and His168, which has characteristics of protein structures of Fe/Mn SODs family. Cloning and bioinformatics analysis of A. acidoterrestris Fe-SOD will provide information for constructing prokaryotic expression vector and obtaining the gene engineering bacteria strains of producing heat and acid resistant SOD.

河南省基础与前沿技术研究计划项目（142300410137）；河南省高等学校青年骨干教师资助计划项目（2011GGJS-131）