[Subunit structure of AMP-deaminase from skeletal muscles]

AMP-deaminase was purified from skeletal muscle of rat by the affinity chromatography on phosphocellulose and gel-filtration on Sephadex G-200. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate (SDS-PAGE) has shown three protein bands on each step of purification. One of them corresponds to the subunit of tetrameric AMP-deaminase molecule with molecular weight of 76 kDa and two others--to the protein subunit with molecular weight of 42 and 33 kDa. Repeated SDS-PAGE of the main subunit band has revealed again all these protein bands. The data obtained indicate that AMP-deaminase subunit of 76 kDa is able to dissociate on two polypeptide chains with similar values of molecular weights in the presence of SDS.