In:
Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 116, No. 9 ( 2019-02-26), p. 3572-3577
Kurzfassung:
Cytochrome c oxidase (C c O) reduces dioxygen to water and harnesses the chemical energy to drive proton translocation across the inner mitochondrial membrane by an unresolved mechanism. By using time-resolved serial femtosecond crystallography, we identified a key oxygen intermediate of bovine C c O. It is assigned to the P R -intermediate, which is characterized by specific redox states of the metal centers and a distinct protein conformation. The heme a 3 iron atom is in a ferryl (Fe 4+ = O 2− ) configuration, and heme a and Cu B are oxidized while Cu A is reduced. A Helix-X segment is poised in an open conformational state; the heme a farnesyl sidechain is H-bonded to S382, and loop-I-II adopts a distinct structure. These data offer insights into the mechanism by which the oxygen chemistry is coupled to unidirectional proton translocation.
Materialart:
Online-Ressource
ISSN:
0027-8424
,
1091-6490
DOI:
10.1073/pnas.1814526116
Sprache:
Englisch
Verlag:
Proceedings of the National Academy of Sciences
Publikationsdatum:
2019
ZDB Id:
209104-5
ZDB Id:
1461794-8
SSG:
11
SSG:
12
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