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? subunit of Bacillus subtilis F1-ATPase relieves MgADP inhibition.

ABSTRACT: MgADP inhibition, which is considered as a part of the regulatory system of ATP synthase, is a well-known process common to all F1-ATPases, a soluble component of ATP synthase. The entrapment of inhibitory MgADP at catalytic sites terminates catalysis. Regulation by the ? subunit is a common mechanism among F1-ATPases from bacteria and plants. The relationship between these two forms of regulatory mechanisms is obscure because it is difficult to distinguish which is active at a particular moment. Here, using F1-ATPase from Bacillus subtilis (BF1), which is strongly affected by MgADP inhibition, we can distinguish MgADP inhibition from regulation by the ? subunit. The ? subunit did not inhibit but activated BF1. We conclude that the ? subunit relieves BF1 from MgADP inhibition.

SUBMITTER: Mizumoto J

PROVIDER: S-EPMC3742539 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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ε subunit of Bacillus subtilis F1-ATPase relieves MgADP inhibition.

Mizumoto Junya J Kikuchi Yuka Y Nakanishi Yo-Hei YH Mouri Naoto N Cai Anrong A Ohta Tokushiro T Haruyama Takamitsu T Kato-Yamada Yasuyuki Y

PloS one 20130813 8

MgADP inhibition, which is considered as a part of the regulatory system of ATP synthase, is a well-known process common to all F1-ATPases, a soluble component of ATP synthase. The entrapment of inhibitory MgADP at catalytic sites terminates catalysis. Regulation by the ε subunit is a common mechanism among F1-ATPases from bacteria and plants. The relationship between these two forms of regulatory mechanisms is obscure because it is difficult to distinguish which is active at a particular moment ...[more]

PMID: 23967352

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