Crystallographic and online spectral evidence for role of conformational change and conserved water in cytochrome oxidase proton pump.

ABSTRACT: Crystal structures in both oxidized and reduced forms are reported for two bacterial cytochrome c oxidase mutants that define the D and K proton paths, showing conformational change in response to reduction and the loss of strategic waters that can account for inhibition of proton transfer. In the oxidized state both mutants of the Rhodobacter sphaeroides enzyme, D132A and K362M, show overall structures similar to wild type, indicating no long-range effects of mutation. In the reduced state, the mutants show an altered conformation similar to that seen in reduced wild type, confirming this reproducible, reversible response to reduction. In the strongly inhibited D132A mutant, positions of residues and waters in the D pathway are unaffected except in the entry region close to the mutation,

SUBMITTER: Liu J 

PROVIDER: S-EPMC3029696 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature