拟南芥高丝氨酸激酶HSK的分子结构与同源建模研究  

A Study on Molecular Structure and Homology Modeling of Homoserine Kinase( HSK) from Arabidopsis thaliana

作　　者：肖文君[1] 胡帅[1] 曾荣[2] 常洪平[1] 袁聪颖[1] 王萍[1] 张骋[1] 陆秀涛[1] 郭新红[1] 

机构地区：[1]湖南大学生物学院植物功能基因组学与发育调控湖南省重点实验室,湖南长沙410082 [2]湖南大学金融与统计学院,湖南长沙410079

出　　处：《激光生物学报》2014年第2期147-154,共8页Acta Laser Biology Sinica

基　　金：国家自然科学基金项目(31071076;30871325);高等学校博士学科点专项科研基金博导类课题(20130161110005);教育部新世纪优秀人才支持计划项目(NCET-10-0363);湖南省杰出青年基金项目(11JJ1005);教育部留学回国人员科研启动基金项目([2011]1139);湖南大学20013年大学生创新训练(SIT)计划项目(2013019)

摘　　要：高丝氨酸激酶(EC 2.7.1.39)是拟南芥中合成甲硫氨酸和苏氨酸的关键酶之一。作者利用DNAMAN软件分析高丝氨酸激酶的氨基酸组成和等电点;利用生物信息学在线网站预测分析其疏水性、二级结构、跨膜结构域、信号肽区域、PEST序列、化学修饰位点及亚细胞定位等;利用SWISS-MODEL软件进行同源建模,使用Chimera(V1.8.1)做结构修饰处理,最后利用Molprobity4及ERRAT(V2.0)对建模结果进行结构质量分析。结果发现:HSK预测等电点为8.48,平均亲水性0.267;二级结构中α-螺旋占34.32%,不规则卷曲占48.11%,延伸链占17.57%;高丝氨酸激酶的预测模型经验证具有稳定的空间结构,符合立体化学规则。Homoserine Kinase （EC 2.7.1.39, HSK） is among the key enzymes involved in the biosynthesis of Met and Thr in Arabidopsis thaliana. In this study, we analyzed the amino acid composition and iso-electric point of HSK by DNAMAN software, and its physicoehemical and structural properties e.g. secondary structures, hydrophobicity, transmembrane domains, signal peptide, PEST sequences, Chemically modified sites as well as subcellular localization were predicted using bioinformatics websites. Homology modeling was done utilizing SWISS-MODEL, structurally modified using Chimera（ V1.8.1 ） and checked quality by Molprobityd and ERRAT（ V 2.0）. The results showed that the pI ofHSK was 8.48. The positive GRAVY score value, 0. 267, ensured its better hydropathicity. Random coil was dominated, reaching 48.11% , in secondary structure of HSK and α-helix 34.32% , extended strand 17.57%. The homology modeling structure was verified to be stable and met the rules of stereochemistry.

关 键 词：拟南芥 高丝氨酸激酶 分子结构 同源建模 

分 类 号：Q786[生物学—分子生物学]