Location of an essential carboxyl group along the heavy chain of cardiac and skeletal myosin subfragments 1

Biochemistry. 1983 Dec 6;22(25):5843-7. doi: 10.1021/bi00294a024.


Cardiac and skeletal myosin subfragments 1 cleaved into three fragments were modified by 1-cyclohexyl-3-(2-morpholinoethyl)carbodiimide metho-p-toluene-sulfonate in the presence of the nucleophile nitrotyrosine ethyl ester. The effects observed (first-order kinetics of ATPase inactivation, incorporation of 1 mol of nitrotyrosine/mol of subfragment 1) were similar to those previously observed for the nondigested subfragments 1 [Lacombe, G., Van Thiem, N., & Swynghedauw, B. (1981) Biochemistry 20, 3648-3653; Körner, M., Van Thiem, N., Lacombe, G., & Swynghedauw, B. (1982) Biochem. Biophys. Res. Commun. 105, 1198-1207]. For both native and digested subfragments 1, which were inactivated to the extent of about 70%, the location of the label nitrotyrosine was performed by immunological blotting with 125I-labeled anti-nitrotyrosine immunoglobulins. It was found that the modified residue was essentially located on the heavy chain for the native subfragments 1 and on the 50K peptide for the digested subfragments 1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CME-Carbodiimide / analogs & derivatives
  • CME-Carbodiimide / pharmacology
  • Dogs
  • Muscles / analysis*
  • Myocardium / analysis*
  • Myosin Subfragments
  • Myosins / analysis*
  • Peptide Fragments / analysis*
  • Tyrosine / analogs & derivatives
  • Tyrosine / pharmacology


  • Myosin Subfragments
  • Peptide Fragments
  • CME-Carbodiimide
  • Tyrosine
  • nitrotyrosine ethyl ester
  • Myosins