title: Intermediate complex of ATP hydrolysis and synthesis by muscle proteins.
abstract: Myosin catalyzed exchange between 32Pi and ATP in reaction medium during its enzymatic hydrolysis of ATP only by a very small amount. Addition of actin increased to a great extent the rate of incorporation of 32Pi in the presence of Mg. Glycerinated smooth muscle fibers also exhibited the ability to exchange 32Pi and ATP upon the application of external force (repeated stretching and releasing). A schematic mechanism of the action of actin and external force on acceleration of 32Pi incorporation is proposed and the importance of the M-ADP complex for force generation is suggested.
mesh_terms: D000199:Actins / Q000494:pharmacology*; D000251:Adenosine Triphosphatases / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000096:biosynthesis / Q000378:metabolism*; D000818:Animals; D003106:Colon; D011756:Diphosphates / Q000378:metabolism; D008954:Models, Biological; D009119:Muscle Contraction; D009130:Muscle, Smooth / Q000201:enzymology*; D009218:Myosins / Q000378:metabolism; D011817:Rabbits
chemical_list: D000199:Actins; D011756:Diphosphates; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; D009218:Myosins