2012 Fiscal Year Final Research Report

Analysis of protein folding memory with modification of intramolecular chaperons and its application

Research Project

Project/Area Number	24656501
Research Category	Grant-in-Aid for Challenging Exploratory Research
Allocation Type	Multi-year Fund
Research Field	Biofunction/Bioprocess
Research Institution	Kyoto University
Principal Investigator	UEDA Mitsuyoshi 京都大学, 大学院・農学研究科, 教授 (90183201)
Project Period (FY)	2012
Keywords	プロテインフォールディングメモリー / プロペプチド / 分子内シャペロン / カルボキシペプチダーゼ Y / 分子ディスプレイ / 活性化エネルギー / アンフィンセン理論 / 触媒効率
Research Abstract	CPYs (carboxypeptidase Y) with mutated propeptides were successfully displayed on yeast cell surface, and the mature enzymes were purified by the selective cleavage of mutated propeptides. Measurement of the activity and kinetics of the displayed CPYs indicated that the propeptide mutation altered the catalytic efficiency of mCPY. Although the mature region of the wild -type and mutant CPYs had identical amino acid sequences, the mCPYs from the mutant proCPYs had higher catalytic efficiency than the wild-type. These results indicate that proteins with identical amino acid sequence can fold into isomeric proteins with micro-conformational changes through mutated intramolecular chaperones.