title: [18 O-exchange reactions catalyzed by myosin of calf intestine smooth muscle].
abstract: 18O-exchange reactions of smooth muscle myosin of calf intestine were studied. Smooth muscle myosin, similar to skeletal myosin, catalyses two types of 18O-exchange reactions--intermediate and direct. Only quantitative differences of the exchange intensity are observed. 18O-exchange dependence on bivalent cation and nucleotide nature is found. The comparison of 18O-exchange characteristics for myosins of smooth and skeletal muscles confirms the hypothesis on the similarity of molecular mechanisms of ATP hydrolysis by myosin from different muscle types.
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D002384:Catalysis; D002413:Cations, Divalent; D002417:Cattle; D006868:Hydrolysis; D007413:Intestinal Mucosa / Q000378:metabolism; D009130:Muscle, Smooth / Q000378:metabolism*; D009132:Muscles / Q000033:anatomy & histology / Q000378:metabolism; D009218:Myosins / Q000378:metabolism*; D009711:Nucleotides / Q000494:pharmacology; D010100:Oxygen
chemical_list: D002413:Cations, Divalent; D009711:Nucleotides; D000255:Adenosine Triphosphate; D009218:Myosins; D010100:Oxygen
vernacular_title: O 18-obmennye reaktsii, kataliziruemye miozinom gladkikh myshts kishechnika telenka.