Complex structure of cytochrome c-cytochrome c oxidase reveals a novel protein-protein interaction mode.
EMBO J
; 36(3): 291-300, 2017 02 01.
Article
em En
| MEDLINE
| ID: mdl-27979921
ABSTRACT
Mitochondrial cytochrome c oxidase (CcO) transfers electrons from cytochrome c (Cyt.c) to O2 to generate H2O, a process coupled to proton pumping. To elucidate the mechanism of electron transfer, we determined the structure of the mammalian Cyt.c-CcO complex at 2.0-Å resolution and identified an electron transfer pathway from Cyt.c to CcO. The specific interaction between Cyt.c and CcO is stabilized by a few electrostatic interactions between side chains within a small contact surface area. Between the two proteins are three water layers with a long inter-molecular span, one of which lies between the other two layers without significant direct interaction with either protein. Cyt.c undergoes large structural fluctuations, using the interacting regions with CcO as a fulcrum. These features of the protein-protein interaction at the docking interface represent the first known example of a new class of protein-protein interaction, which we term "soft and specific". This interaction is likely to contribute to the rapid association/dissociation of the Cyt.c-CcO complex, which facilitates the sequential supply of four electrons for the O2 reduction reaction.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Complexo IV da Cadeia de Transporte de Elétrons
/
Citocromos c
Limite:
Animals
Idioma:
En
Revista:
EMBO J
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Japão