2ck3
Azide inhibited bovine F1-ATPaseAzide inhibited bovine F1-ATPase
Structural highlights
FunctionATPA_BOVIN Mitochondrial membrane ATP synthase (F(1)F(0) ATP synthase or Complex V) produces ATP from ADP in the presence of a proton gradient across the membrane which is generated by electron transport complexes of the respiratory chain. F-type ATPases consist of two structural domains, F(1) - containing the extramembraneous catalytic core, and F(0) - containing the membrane proton channel, linked together by a central stalk and a peripheral stalk. During catalysis, ATP synthesis in the catalytic domain of F(1) is coupled via a rotary mechanism of the central stalk subunits to proton translocation. Subunits alpha and beta form the catalytic core in F(1). Rotation of the central stalk against the surrounding alpha(3)beta(3) subunits leads to hydrolysis of ATP in three separate catalytic sites on the beta subunits. Subunit alpha does not bear the catalytic high-affinity ATP-binding sites (By similarity). Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedIn the structure of bovine F1-ATPase determined at 1.95-A resolution with crystals grown in the presence of ADP, 5'-adenylyl-imidodiphosphate, and azide, the azide anion interacts with the beta-phosphate of ADP and with residues in the ADP-binding catalytic subunit, betaDP. It occupies a position between the catalytically essential amino acids, beta-Lys-162 in the P loop and the "arginine finger" residue, alpha-Arg-373, similar to the site occupied by the gamma-phosphate in the ATP-binding subunit, betaTP. Its presence in the betaDP-subunit tightens the binding of the side chains to the nucleotide, enhancing its affinity and thereby stabilizing the state with bound ADP. This mechanism of inhibition appears to be common to many other ATPases, including ABC transporters, SecA, and DNA topoisomerase IIalpha. It also explains the stimulatory effect of azide on ATP-sensitive potassium channels by enhancing the binding of ADP. How azide inhibits ATP hydrolysis by the F-ATPases.,Bowler MW, Montgomery MG, Leslie AG, Walker JE Proc Natl Acad Sci U S A. 2006 Jun 6;103(23):8646-9. Epub 2006 May 25. PMID:16728506[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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