Millisecond time resolution electron cryo-microscopy of the M-ATP transient kinetic state of the acto-myosin ATPase.
The structure of the AM-ATP transient kinetic state of the acto-myosin ATPase cycle has been examined by electron microscopy using frozen-hydrated specimens prepared in low ionic strength. By spraying grids layered with the acto-S1 complex with ATP immediately before freezing, it was possible to examine the structure of the ternary complex with a time resolution of 10 ms. Disordered binding of the S1 was observed, suggesting more than one attachment geometry. This could be due to the presence of more than one biochemical intermediate, or to a single intermediate binding in more than one conformation.
Walker
M
M
Muscle and Collagen Group, Bristol University Veterinary School, Langford, United Kingdom.
Trinick
J
J
White
H
H
D000255:Adenosine Triphosphate / Q000031:analogs & derivatives / Q000378:metabolism*; D000818:Animals; D055592:Biophysical Phenomena; D001703:Biophysics; D005615:Freezing; D006868:Hydrolysis; D066298:In Vitro Techniques; D007700:Kinetics; D008854:Microscopy, Electron; D008954:Models, Biological; D009119:Muscle Contraction / Q000502:physiology; D015879:Myosin Subfragments / Q000378:metabolism / Q000502:physiology / Q000648:ultrastructure; D009218:Myosins / Q000378:metabolism* / Q000502:physiology / Q000648:ultrastructure*; D009994:Osmolar Concentration; D013552:Swine; D062367:ortho-Aminobenzoates
D015879:Myosin Subfragments; D062367:ortho-Aminobenzoates; C045473:3'-O-(N-methylanthraniloyl) ATP; D000255:Adenosine Triphosphate; D009218:Myosins