SmTPS功能解析及其催化丹参萜类化合物多样性的形成机制研究

结构丰富的萜类化合物是新药研发的重要化合物资源，而萜类合酶（TPS）是合成萜类化合物骨架结构的关键酶。系统解析基因组中TPS的功能将为获得新结构类型萜类化合物奠定基础。基于课题组完成的丹参基因组图谱，申请人构建了从丹参TPS（SmTPS）基因的系统发现、到异源表达及催化产物鉴定的研究体系，预实验证明一些SmTPS具有产物多样性的催化特点。本项目将在系统鉴定丹参基因组中全部SmTPS的催化产物基础上，分析其产物多样性信息，选择序列同源性高而产物差异大的TPS作为研究对象，通过三维同源建模选择TPS活性位点附近与底物结合的关键氨基酸，对其进行定点突变构建突变酶，检测突变酶的产物多样性变化，阐明影响SmTPS产物多样性的分子结构基础。本研究将为发掘新萜类化合物提供新途径，也为通过酶工程、合成生物学等技术改变TPS结构、合成新结构类型或新活性萜类化合物研究奠定基础，具有重要科学意义和良好应用前景。

Structurally rich terpenoids are important resources for new drug research and development.Terpene synthase (TPS) is a key enzyme for the synthesis of terpenoid skeleton structure. Systematic analysis of the function of TPS in genome will lay a foundation for obtaining new structural terpenoids. Based on the genome of Salvia miltiorrhiza, the applicant constructed a system of systematic discovery, heterologous expression and identification of catalytic products of SmTPS. Pre-experiments showed that some SmTPS had catalytic characteristics of product diversity. This project will systematically identify all the catalytic products of SmTPS in S. miltiorrhiza genome, analyze the product diversity information, select TPS with high sequence homology and significant product difference as the research object, and find the key amino acid sites near the active site of TPS binding to substrate through three-dimensional homology modeling. Through site-directed mutagenesis, mutant enzymes will be constructed and detected. Based on the variation of product diversity for the mutant and wild-type enzymes, and the molecular structure basis affecting the product diversity of SmTPS will be illustrated. This study will provide a new way to discover new terpenoids, and lay a foundation for the study of TPS structure modification and synthesis of new structural types or new active terpenoids by enzymatic engineering and synthetic biology. This project possesses important scientific significance and application prospects.