학술논문
ATP binding induces large conformational changes in the apical and equatorial domains of the eukaryotic chaperonin containing TCP-1 complex.
Document Type
Article
Source
Journal of Biological Chemistry; April 1998, Vol. 273 Issue: 17 p10091-4, 4p
Subject
Language
ISSN
00219258; 1083351X
Abstract
The chaperonin-containing TCP-1 complex (CCT) is a heteromeric particle composed of eight different subunits arranged in two back-to-back 8-fold pseudo-symmetric rings. The structural and functional implications of nucleotide binding to the CCT complex was addressed by electron microscopy and image processing. Whereas ADP binding to CCT does not reveal major conformational differences when compared with nucleotide-free CCT, ATP binding induces large conformational changes in the apical and equatorial domains, shifting the latter domains up to 40 degrees (with respect to the inter-ring plane) compared with 10 degrees for nucleotide-free CCT or ADP-CCT. This equatorial ATP-induced shift has no counterpart in GroEL, its prokaryotic homologue, which suggests differences in the folding mechanism for CCT.