苏云金杆菌Ⅰ型抗癌晶体蛋白的分子模建  

Molecular Modeling of Cancer Cell-Killing Crystal Protein Parasporin-1 from Bacillus thuringiensis

作　　者：袁宇熹[1] 张同武[1] 陈智山[1] 林毅[1] 

机构地区：[1]华侨大学化工学院,福建泉州362021

出　　处：《华侨大学学报（自然科学版）》2009年第4期420-424,共5页Journal of Huaqiao University(Natural Science)

基　　金：国家自然科学基金资助项目(40601046);细胞生物学与肿瘤细胞工程教育部重点实验室开放基金资助项目(B0510011)

摘　　要：通过同源建模,得到Ⅰ型抗癌晶体蛋白Parasporin-1的初始三维结构.经分子动力学方法优化后,利用Ramachandran Plot检测和结构匹配等方法对模型进行评价.结果显示,结构模型中的键长、键角及二面角的分布合理,与模板蛋白的主链α碳原子的均方根差值为0.537 592,在合理范围之内.此外,通过分析Paras-porin-1结构域Ⅰ中的-βloop-β结构片段,推测出第2个蛋白酶处理激活位点的位置在两个芳香族疏水性氨基酸F167与Y168之间.The structure of Parasporin-1, the first cancer cell-killing crystal protein from Bacillus thuringiensis, was constructed using homology modeling, and was optimized by molecular mechanics method. The simulated structure was evaluated using Ramachandran Plot and structural matching. The distributions of bond length, bond angel, and dihedral angle were rational. The RMSD （root-mean-square deviation） value of a-carbon atom on the main chain between Parasporin-1 and model protein was 0. 537 592, which was within reasonable bounds. The analysis of β-loop-β motif in Domain I suggest that the second site digested by proteinase K were located between F167 and Y168.

关 键 词：Ⅰ型抗癌晶体蛋白 同源建模 分子动力学模拟 蛋白酶 激活位点 

分 类 号：Q811.4[生物学—生物工程] Q71