Proposal of hybrid-type chaperonin reaction mechanism in response to the intracellular environment

2015 Fiscal Year Final Research Report

• Project/Area Number: 25440055
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Functional biochemistry
• Research Institution: Kanagawa Institute of Technology
• Principal Investigator: KOIKE AYUMI 神奈川工科大学, 応用バイオ科学部, 教授 (20454176)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: タンパク質フォールディング / シャペロニン

Outline of Final Research Achievements

GroEL is able to use both the “bullet cycle” and the “football cycle”, the selection will depend on the situation in the cell. We determined the crystal structure of the “football” GroEL:GroES2 complex. The overall structure of the “football” complex resembled the GroES-bound GroEL-ring of the asymmetric 1:1 GroEL:GroES complex (the “bullet” complex). However, the two GroES-bound GroEL-rings form a modified interface by a rotation about the 7-fold axis. As a result, the inter-ring contacts between the two GroEL rings in the football complex differed from those in the bullet complex. The altered inter-GroEL ring contacts in the football structure lead GroEL tetradecamer to dissociated in the presence of ATP and GroES in a native gel.
Furthermore, we constructed coexpression system of distinct fluorescence molecules-labeled GroES in E. coli for the purpose of detection of the football-like reaction intermediates by FCCS.

Free Research Field

生化学