The structure of bovine F1-ATPase complexed with the antibiotic inhibitor aurovertin B.
In the structure of bovine mitochondrial F1-ATPase that was previously determined with crystals grown in the presence of adenylyl-imidodiphosphate (AMP-PNP) and ADP, the three catalytic beta-subunits have different conformations and nucleotide occupancies. Adenylyl-imidodiphosphate is bound to one beta-subunit (betaTP), ADP is bound to the second (betaDP), and no nucleotide is bound to the third (betaE). Here we show that the uncompetitive inhibitor aurovertin B binds to bovine F1 at two equivalent sites in betaTP and betaE, in a cleft between the nucleotide binding and C-terminal domains. In betaDP, the aurovertin B pocket is incomplete and is inaccessible to the inhibitor. The aurovertin B bound to betaTP interacts with alpha-Glu399 in the adjacent alphaTP subunit, whereas the aurovertin B bound to betaE is too distant from alphaE to make an equivalent interaction. Both sites encompass betaArg-412, which was shown by mutational studies to be involved in binding aurovertin. Except for minor changes around the aurovertin pockets, the structure of bovine F1-ATPase is the same as determined previously. Aurovertin B appears to act by preventing closure of the catalytic interfaces, which is essential for a catalytic mechanism involving cyclic interconversion of catalytic sites.
van Raaij
M J
MJ
Medical Research Council Laboratory of Molecular Biology, Cambridge, United Kingdom.
Abrahams
J P
JP
Leslie
A G
AG
Walker
J E
JE
D000266:Adenylyl Imidodiphosphate / Q000494:pharmacology; D000818:Animals; D001120:Arginine; D001313:Aurovertins / Q000737:chemistry* / Q000378:metabolism*; D001665:Binding Sites; D002417:Cattle; D018360:Crystallography, X-Ray; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000378:metabolism; D018698:Glutamic Acid; D046911:Macromolecular Substances; D008958:Models, Molecular; D015394:Molecular Structure; D009206:Myocardium / Q000201:enzymology; D017433:Protein Structure, Secondary; D006180:Proton-Translocating ATPases / Q000737:chemistry* / Q000378:metabolism*
D001313:Aurovertins; D004791:Enzyme Inhibitors; D046911:Macromolecular Substances; D000266:Adenylyl Imidodiphosphate; D018698:Glutamic Acid; C034402:aurovertin B; D001120:Arginine; D006180:Proton-Translocating ATPases