title: The sulfhydryl groups involved in the active site of myosin B adenosinetriphosphatase. IV. Structure around the Sa thiol group.
abstract: The structure of a tryptic peptide containing one specific sulfhydryl group (Sa), which is responsible for the activation of Mg2+-ATPase of myosin B and is present in the light meromyosin region of the myosin molecule, was studied. The amino acid sequence was deduced to be Thr (or Ser)-Asn-Ala-Ala-Cys-Ala-Ala-Leu-Asp-Lys-Lys. In addition, a space-filling model around Sa was built up by comparing Sa-peptide with the amino acid sequence around Cys 190 of alpha-tropomyosin, and the high reactivity of Sa with N-ethylmaleimide is considered based on this model.
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D001665:Binding Sites; D005033:Ethylmaleimide / Q000494:pharmacology; D008958:Models, Molecular; D009132:Muscles / Q000201:enzymology; D009218:Myosins; D010446:Peptide Fragments / Q000302:isolation & purification; D011817:Rabbits; D013438:Sulfhydryl Compounds / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D000596:Amino Acids; D010446:Peptide Fragments; D013438:Sulfhydryl Compounds; D000251:Adenosine Triphosphatases; D009218:Myosins; D005033:Ethylmaleimide