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Complex cooperativity of ATP hydrolysis in the F1-ATPase molecular motor

Ming S. Liu·B. D. Todd·Richard J. Sadus
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Abstract

F1-ATPase catalyses ATP hydrolysis and converts the cellular chemical energy into mechanical rotation. The hydrolysis reaction in F1-ATPase does not follow the widely believed Michaelis-Menten mechanism. Instead, the hydrolysis mechanism behaves in an ATP-dependent manner. We develop a model for enzyme kinetics and hydrolysis cooperativity of F1-ATPase which involves the binding-state changes to the coupling catalytic reactions. The quantitative analysis and modeling suggest the existence of complex cooperative hydrolysis between three different catalysis sites of F1-ATPase. This complexity may be taken into account to resolve the arguments on the bindingchange mechanism in F1-ATPase.

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Ming S. Liu, B. D. Todd, Richard J. Sadus. 2004-01-21. Complex cooperativity of ATP hydrolysis in the F1-ATPase molecular motor. https://arxiv.org/abs/q-bio/0401027

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