Functionally distinct beta subunits in F1-adenosinetriphosphatase.

J H Wang

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PubMed · 2857175

Functionally distinct beta subunits in F1-adenosinetriphosphatase.

J H Wang

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Abstract

A method has been developed for the effective inactivation of bovine heart mitochondrial F1-ATPase (MF1) by partially dissociating its subunits with 3 M LiCl at 0 degree C and for the subsequent partial restoration of its ATPase activity by making the subunits reassociate upon the removal of LiCl by centrifugal gel filtration at room temperature through Sephadex G-25-80 which has been pre-equilibrated with buffer containing 3 mM ATP. When covalently labeled MF1 with approximately one 7-[4-nitro-2,1,3-benzoxadiazole] label/MF1 was subjected to this type of partial dissociation-reassociation treatment, its ATPase activity could be increased from 1.48 to 18.0 mumol of ATP min-1 mg-1 without losing the covalent label. The experimental results are incompatible with models for F1-ATPase with either 3 or 2 equivalent alternating catalytic sites, but are consistent with the model with 1 active catalytic site and 2 interacting regulatory sites.

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4-Chloro-7-nitrobenzofurazan Animals Binding Sites Cattle Chemical Phenomena Chemistry Chlorides Chromatography, Gel Dithiothreitol Enzyme Activation Lithium Lithium Chloride Macromolecular Substances Mitochondria, Heart Proton-Translocating ATPases Journal Article Research Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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J H Wang. 1985-02-10. Functionally distinct beta subunits in F1-adenosinetriphosphatase.. https://pubmed.ncbi.nlm.nih.gov/2857175/

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