大戟科植物鲨烯环氧酶核苷酸及其编码氨基酸序列生物信息学分析  

Bioinformatics Analysis of Squalene Epoxidase Coding Gene and Amino Acid Sequence in Euphorbiaceae

作　　者：王学方[1] 景炳年 周雍 王伟[1] 魏磊[1] WANG Xuefang;JING Bingnian;ZHOU Yong;WANG Wei;WEI Lei(Biological Developing Center of Henan Academy of Sciences,Henan Plant Natural Products Development Engineering Technology Center,Zhengzhou 450002,China)

机构地区：[1]河南省生物技术开发中心河南省植物天然产物开发工程技术研究中心

出　　处：《河南科学》2019年第7期1082-1089,共8页Henan Science

基　　金：河南省科技计划项目(182102310061);河南省科学院基本科研项目(18JK16015,190613032)

摘　　要：鲨烯环氧酶(squalene epoxidase,SQE)是在三萜和甾醇类化合物生物合成通路中的关键酶.主要采用生物信息学方法对17种大戟科植物的SQE核苷酸及其编码氨基酸序列的序列结构、理化特性方面以及空间结构进行了初步预测和分析,并构建SQE蛋白家族的系统进化树.结果表明,17种大戟科植物的SQE氨基酸序列结构与理化性质具有一定差异,多为碱性的疏水性蛋白;多数不具有信号肽,没有导肽分裂位点,却具有导肽,具有0~5个数量不等的跨膜结构域;亚细胞定位预测可能定位在内质网膜、质膜、类囊体膜和线粒体内膜上. SQE二级结构中最主要的结构元件是α螺旋和无规则卷曲,保守区都含有一个PLN02985 superfamily保守结构域,属于鲨烯单加氧酶超家族.分析结果可为SQE的酶学特性及三萜类化合物生物合成的分子机制研究提供理论基础.Squalene epoxidase(SQE)is one of the important key enzymes in the biosynthesis pathway of triterpenoids and sterols. Seventeen Euphorbiaceae genus SQE in Genebank were analyzed in this article. The nucleic acid and amino acid sequences,physicochemical properties and spatial structures were predicted by using bioinformatics methods. Phylogenetic tree was constructed for SQE protein family. The results showed that the physical and chemical properties of SQE amino acid sequence had certain differences,mainly alkaline hydrophobic protein,there existed transmembrane topological structures,no signal peptide but leader peptide,which mainly located in endoplasmic reticulum membrane,plasma membrane,thylakoid membrane and mitochondrial inner membrane. The main secondary structure of the proteins are α-helix and random coil. All the proteins have a PLN02985 superfamily conserved domain,belonging to the squalene monooxygenase superfamily. The results provide theoretical basis for study on both the enzymatic characteristics of SQE and the biosynthesis pathway of triterpenoid.

关 键 词：大戟科 生物信息学 鲨烯环氧酶 三萜生物合成 

分 类 号：R931[医药卫生—生药学]