title: [Kinetic analysis of hydrolysis of free ATP and MgATP by natural actomyosin].
abstract: Computer analysis of experimental data published in 1-3 allowed to establish the presence of two non-interacting inequivalent hydrolytic sites in actomyosin molecule, one of them being specific for binding and hydrolysis of free ATP, the other--for MgATP. Thus both species of ATP are the substrates of actomyosin ATPase. Actomyosin molecule seems to bind on more (in additon to two active sites) substrate molecule (MgATP) at some non-catalytic regulatory site. The formation of the enzyme-substrate complex having three ATP molecules (one molecule of free ATP and two--of MgATP) is accompanied by the loss of the activity. An approach to the research of kinetic equations for complex systems considerably decreasing a number of variations to consider is given in this work.
mesh_terms: D000205:Actomyosin / Q000378:metabolism*; D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism*; D001665:Binding Sites; D006868:Hydrolysis; D007700:Kinetics; D008274:Magnesium; D011485:Protein Binding; D013329:Structure-Activity Relationship
chemical_list: D000255:Adenosine Triphosphate; D000205:Actomyosin; D000251:Adenosine Triphosphatases; D008274:Magnesium
vernacular_title: Analiz kinetiki gidroliza svobodnoĭ ATP i Mg-ATP estestvennym aktomiozinom