+検索条件
-Structure paper
タイトル | A mutant chaperonin with rearranged inter-ring electrostatic contacts and temperature-sensitive dissociation. |
---|---|
ジャーナル・号・ページ | Nat Struct Mol Biol, Vol. 11, Issue 11, Page 1128-1133, Year 2004 |
掲載日 | 2004年10月10日 |
![]() | B Trevor Sewell / Robert B Best / Shaoxia Chen / Alan M Roseman / George W Farr / Arthur L Horwich / Helen R Saibil / ![]() |
PubMed 要旨 | The chaperonin GroEL assists protein folding through ATP-dependent, cooperative movements that alternately create folding chambers in its two rings. The substitution E461K at the interface between ...The chaperonin GroEL assists protein folding through ATP-dependent, cooperative movements that alternately create folding chambers in its two rings. The substitution E461K at the interface between these two rings causes temperature-sensitive, defective protein folding in Escherichia coli. To understand the molecular defect, we have examined the mutant chaperonin by cryo-EM. The normal out-of-register alignment of contacts between subunits of opposing wild-type rings is changed in E461K to an in-register one. This is associated with loss of cooperativity in ATP binding and hydrolysis. Consistent with the loss of negative cooperativity between rings, the cochaperonin GroES binds simultaneously to both E461K rings. These GroES-bound structures were unstable at higher temperature, dissociating into complexes of single E461K rings associated with GroES. Lacking the allosteric signal from the opposite ring, these complexes cannot release their GroES and become trapped, dead-end states. |
![]() | ![]() ![]() |
手法 | EM (単粒子) |
解像度 | 25.0 Å |
構造データ | ![]() EMDB-1095: |
由来 |
|