1nbm
From Proteopedia
THE STRUCTURE OF BOVINE F1-ATPASE COVALENTLY INHIBITED WITH 4-CHLORO-7-NITROBENZOFURAZAN
Structural highlights
Function[ATPG_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. Part of the complex F(1) domain and the central stalk which is part of the complex rotary element. The gamma subunit protrudes into the catalytic domain formed of alpha(3)beta(3). 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. [ATPA_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). [ATPB_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. 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 PubMedBACKGROUND: F1-ATPase is the globular domain of F1F0-ATP synthase that catalyses the hydrolysis of ATP to ADP and phosphate. The crystal structure of bovine F1-ATPase has been determined previously to 2.8 A resolution. The enzyme comprises five different subunits in the stoichiometry alpha 3 beta 3 gamma delta epsilon; the three catalytic beta subunits alternate with the three alpha subunits around the centrally located single gamma subunit. To understand more about the catalytic mechanisms, F1-ATPase was inhibited by reaction with 4-chloro-7-nitrobenzofurazan (NBD-Cl) and the structure of the inhibited complex (F1-NBD) determined by X-ray crystallography. RESULTS: In the structure the three beta subunits adopt a different conformation with different nucleotide occupancy. NBD-Cl reacts with the phenolic oxygen of Tyr311 of the beta E subunit, which contains no bound nucleotide. The two other catalytic subunits beta TP and beta DP contain bound adenylyl-imidodiphosphate (AMP-PNP) and ADP, respectively. The binding site of the NBD moiety does not overlap with the regions of beta E that form the nucleotide-binding pocket in subunits beta TP and beta DP nor does it occlude the nucleotide-binding site. Catalysis appears to be inhibited because neither beta TP nor beta DP can accommodate a Tyr311 residue bearing an NBD group. CONCLUSIONS: The results presented here are consistent with a rotary catalytic mechanism of ATP synthesis and hydrolysis, which requires the sequential and concerted participation of all three catalytic sites. NBD-Cl inhibits the enzyme by preventing the modified subunit from adopting a conformation that is essential for catalysis to proceed. Bovine F1-ATPase covalently inhibited with 4-chloro-7-nitrobenzofurazan: the structure provides further support for a rotary catalytic mechanism.,Orriss GL, Leslie AG, Braig K, Walker JE Structure. 1998 Jul 15;6(7):831-7. PMID:9687365[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||||||
