植物萜类合成酶3-羟基-3-甲基戊二酰辅酶A还原酶的生物信息学分析

A bioinformatics analysis on 3-hydroxy-3-methylglutaryle-CoA reductase, a key enzyme in plant isoprenoid biosynthesis

采用生物信息学的方法和工具对已在GenBank上注册的橡胶、烟草、辣椒、穿心莲等植物的萜类合成酶3-羟基-3-甲基戊二酰辅酶A还原酶的核酸及氨基酸序列进行分析,并对其组成成分、信号肽、跨膜拓朴结构域、疏水性/亲水性、蛋白质二级及三级结构、分子系统进化关系等进行预测和推断。结果表明该类酶基因的全长包括5′、3′非翻译区和一个开放阅读框,无信号肽,是一个跨膜的亲水性蛋白,包括两个功能HMG-CoA结合motif及两个功能NADPH结合motif,α-螺旋和不规则盘绕是蛋白质二级结构最大量的结构元件,β-转角和延伸链散布于整个蛋白质中,蛋白质的功能域在空间布局上折叠成“V”形,“V”形的两臂由螺旋状的N结构域和S结构域构成,中间部分由L结构域构成。

In the present study, 3-hydroxy-3-methylglutaryl-CoA reductase from rubber, tobacco, capsicum and andrographis,which were registered in GenBank,were analyzed and predicted by the tools of bioinformatics in the following aspects：the composition of nuclei acid sequences and amino acid sequences, signal peptide, transmembrane topologieal structure,hydrophobicity or hydrophilicity,secondary and tertiary structure of protein, molecular phylogenetic evolution and so on. The results are as follows： the full-length gene of HMGR contains an opening reading frame,5＇-untranstrated region and 3＇-untranstrated region; HMGR is a hyclrophilic and transmembrane protein which lack of signal peptide; the amino acid sequences of HMGR include two functional HMG-CoA binding motifs and two functional NADPH binding motifs; the main motif of predicted secondary structure of HMGR are alpha helix and random coil,beta turn and extended strand are spreaded in the whole secondary structure of protein; the predicted tertiary structure of functional domain of HMGR includes the helical N-domain,S-domain and L-domain.