1.9分辨率μ-crystallin蛋白晶体结构及其酮亚胺还原酶活性位点分析  

Structure of μ-crystallin refined at 1.9- resolution and its ketimine reductase active site analysis

作　　者：许新磊[1] 李健[1] 孙丽华[1] 徐春艳[1] 何建华[1] 

机构地区：[1]中国科学院上海应用物理研究所,上海201800

出　　处：《核技术》2012年第10期721-727,共7页Nuclear Techniques

基　　金：国家自然科学基金(31100528);中国科学院知识创新工程领域前沿基金(O95501C061)资助

摘　　要：采用不同的结晶条件生长了μ-crystallin晶体(CRYM)并解析了人源CRYM与NADPH复合物晶体结构(PDB code 2I99),将分辨率由2.6提高至1.9,修正了2I99的结构。CRYM单体相较2I99结构少3个β折叠和一个310螺旋。NADPH Pro-R面具有多个保守位点可能参与酮亚胺还原酶活性,通过与同源蛋白OCD和AlaDH比对,推测了底物结合位点和催化位点。μ-crystallin, or CRYM, is an NADPH-dependent T3 binding protein in cytosol, has and is of pivotal roles in physiological regulation of thyroid hormone action in vivo. Human CRYM has been identified as ketimine reductase and potential regulated by T3. In this paper, the crystal structure of human CRYM is resolved at 1.9A and compared with 2199. The differences between CRYM monomer and 2199 are three β sheet and two 3 10helixes. The dimerization domain in CRYM presents a cluster of conserved residues side-chain over the Pro-R face of the cofactor NADPH. Compared the overall structure of CRYM with its structural homologs P.putida OCD and A.fulgidus AIaDH, we can deduce ketimine binding site and catalytic site in human CRYM.

关 键 词：T3结合蛋白 晶体结构 酮亚胺还原酶 酶活位点 

分 类 号：Q71[生物学—分子生物学]