Structural mechanism of the recovery stroke in the myosin molecular motor.
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ABSTRACT:
SUBMITTER: Fischer S
PROVIDER: S-EPMC1100758 | biostudies-literature | 2005 May
REPOSITORIES: biostudies-literature
Publications
Structural mechanism of the recovery stroke in the myosin molecular motor.
Fischer Stefan S Windshügel Björn B Horak Daniel D Holmes Kenneth C KC Smith Jeremy C JC
Proceedings of the National Academy of Sciences of the United States of America 20050429 19
The power stroke pulling myosin along actin filaments during muscle contraction is achieved by a large rotation ( approximately 60 degrees ) of the myosin lever arm after ATP hydrolysis. Upon binding the next ATP, myosin dissociates from actin, but its ATPase site is still partially open and catalytically off. Myosin must then close and activate its ATPase site while returning the lever arm for the next power stroke. A mechanism for this coupling between the ATPase site and the distant lever arm ...[more]
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