罗汉果角鲨烯合酶的分子及生化特性

Molecular and biochemical characterization of squalene synthase from Siraitia grosvenorii.

作者信息

Su Heling, Liu Yongming, Xiao Yalun, Tan Yanlian, Gu Yunyan, Liang Bin, Huang Hongli, Wu Yaosheng

机构信息

Department of Biochemistry and Molecular Biology, Guangxi Medical University, Nanning, Guangxi, 530000, China.

Key Laboratory of Medicinal Biotechnology, Guilin Medical University, Guilin, Guangxi, 541004, China.

出版信息

Biotechnol Lett. 2017 Jul;39(7):1009-1018. doi: 10.1007/s10529-017-2328-z. Epub 2017 Mar 28.

DOI:10.1007/s10529-017-2328-z

PMID:28353148

Abstract

OBJECTIVES

To clone and characterize the squalene synthase from Siraitia grosvenorii (SgSQS).

RESULTS

The gene encoding SgSQS was cloned. SgSQS has 417 amino acid residues with an pI of 7.3. There are 32 phosphorylation sites in its sequence: S as well as S play important roles in regulation of enzyme activity. The enzyme is a monomeric protein with a cave-like active center formed by α helixes and has two transmembrane domains at its C-terminus. SgSQS mRNA expression in stem and root were about twice as much as that in leaf and peel. Full-length SgSQS with measurable catalytic activity was expressed in Escherichia coli. SgSQS activity was optimal at 37 °C and pH 7.5 respectively.

CONCLUSION

SgSQS gene was cloned, and the molecular structure and biochemical function of SgSQS were characterized.

摘要

目的

克隆罗汉果鲨烯合酶（SgSQS）并对其进行表征。

结果

克隆了编码SgSQS的基因。SgSQS有417个氨基酸残基，其等电点为7.3。其序列中有32个磷酸化位点：丝氨酸（S）以及苏氨酸（S）在酶活性调节中起重要作用。该酶是一种单体蛋白，具有由α螺旋形成的洞穴状活性中心，并且在其C端有两个跨膜结构域。SgSQS mRNA在茎和根中的表达量约为叶和果皮中的两倍。具有可测量催化活性的全长SgSQS在大肠杆菌中表达。SgSQS活性分别在37°C和pH 7.5时最佳。