title: Identification of the site important for the actin-activated MgATPase activity of myosin subfragment-1.
abstract: The lysine-rich sequence (-KKGGKKK-) located at the 50,000/20,000 Mr junction of myosin subfragment-1 (S-1) was cleaved by endoprotease Arg-C or by trypsin in the presence of ATP and an equimolar amount of actin. Under these conditions, cleavage by Arg-C was between the first and second lysine residues, whereas cleavage by trypsin was between the third and fourth lysine residues. The actin-activated MgATPase activity of the S-1 cleaved by Arg-C was almost the same as native S-1, but S-1 cleaved by trypsin showed markedly reduced ATPase activity.
authors.affiliation: Faculty of Liberal Arts, University of the Air, Chiba, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yamamoto
mesh_terms: D000199:Actins / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D017301:Ca(2+) Mg(2+)-ATPase / Q000378:metabolism / Q000648:ultrastructure; D002645:Chickens; D004789:Enzyme Activation; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D008970:Molecular Weight; D015879:Myosin Subfragments / Q000378:metabolism* / Q000648:ultrastructure; D009218:Myosins / Q000378:metabolism* / Q000648:ultrastructure; D010446:Peptide Fragments / Q000378:metabolism; D013329:Structure-Activity Relationship
chemical_list: D000199:Actins; D015879:Myosin Subfragments; D010446:Peptide Fragments; D017301:Ca(2+) Mg(2+)-ATPase; D009218:Myosins