抗癌晶体蛋白Parasporin-2空间结构的研究  

The 3-D Structure of Crystal Protein Parasporin-2 that is Non-hemolytic but Capable of Preferentially Killing Cancer Cells

作　　者：林毅[1] 张同武[1] 陈智山[1] 蔡福营[1] 

机构地区：[1]华侨大学生物工程与技术系工业生物技术福建省高校重点实验室,福建泉州362021

出　　处：《激光生物学报》2008年第2期181-185,171,共6页Acta Laser Biology Sinica

基　　金：国家自然科学基金项目(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项目(2005103)

摘　　要：通过同源建模得到了抗癌晶体蛋白Parasporin-2(Cry46Aa1)活性区的初始三维结构,利用分子动力学方法对初始三维结构进行优化。为了评估模型的好坏,利用Ramachandran plot和结构匹配等方法对模型进行评价。结果显示,所得的Parasporin-2空间模型良好。比较了Cry46Aa1与Cry46Ab1这两种高度同源的抗癌晶体蛋白的空间结构,找出了其空间结构上的不同之处。通过大分子对接程序Hex4.5,模拟了Parasporin-2与受体GPI-瞄固蛋白(CD59)的相互作用。结果显示,Parasporin-2中参与对接的活性位点位于两个α-螺旋下方的凹槽内,而CD59中的四个loop倾向于插入该凹槽内。研究结果为Parasporin-2的抗癌机制研究及其理性改造奠定了基础。The initial three dimensional structure of Parasporin-2 （ Cry46Aal ） was constructed by homology modeling method, then was optimized by molecular mechanics method. The quality of the structure was evaluated to be good using Ramachandran plot and structural matching. In addition, the structural difference between Cry46Aal and Cry46Abl was presented. The interaction between Parasporin-2 and its receptor, GPI-anchored protein （CD59） , was simulated using macromolecular docking procedures Hex4.5. It showed that the residues in a groove below two α-helixs of Parasporin-2 were responsible for the interaction, and the four loops of CD59 inserted the groove. The results provided a basis for the rational design of Cry46Aal , and help us to understand the interactions between Cry46Aal and cellular receptor.

关 键 词：抗癌晶体蛋白 同源建模 分子动力学模拟 大分子对接 

分 类 号：Q71[生物学—分子生物学]