A phosphorus-31 nuclear magnetic resonance study on the complex of chicken gizzard myosin subfragment 1 with adenosine diphosphate.

The complex of Mg-ADP with chicken gizzard myosin subfragment 1 (S1), obtained by the treatment with Staphylococcus aureus V8 proteinase, was observed with 31P NMR at various temperatures between 0 and 25 degrees C. The signal of S1.ADP complex was observed at -2 to -3 ppm as a rather broad peak. As compared with the results for rabbit skeletal muscle S1.ADP complex (Tanokura M, Ebashi S: J Biochem 113: 19-21, 1993), the signal was assigned to beta-phosphate of ADP in the S1.ADP complex. The signal of the complex was so broad and weak that the dependences on temperature and magnetic field strength were not clear. The observation suggests the tight interaction of S1 with the phosphate moieties of ADP in the complex and the extremely anisotropic distribution of electrons around phosphorus nuclei.