Nature and immunochemical characteristics of a Ca2+/calmodulin kinase activity endowed in a highly insoluble protein purified from adult rat brain.
Using sequential extraction procedure of proteins from adult rat forebrain, a protein of Mr 52,000, insoluble in neutral detergents, capable of binding calmodulin in the presence of Ca2+, was isolated. Antibodies to this antigen had the capacity to inhibit the Ca2+/calmodulin-dependent kinase activity associated with this protein. This protein (52K) (in many respects identical to the major protein of postsynaptic densities) shares by itself the Ca2+/calmodulin-dependent kinase activity, thus differing from soluble Ca2+/calmodulin-dependent kinases isolated by others. Despite its insolubility in most detergents, the 52K protein is not particularly rich in hydrophobic amino acids. Its richness in cysteine and proline residues suggests that the active conformation of the enzyme is sustained by numerous disulfide bridges.
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D000906:Antibodies; D000936:Antigen-Antibody Complex / Q000032:analysis; D001921:Brain / Q000201:enzymology*; D002531:Cerebellum / Q000201:enzymology; D007700:Kinetics; D008970:Molecular Weight; D009928:Organ Specificity; D011494:Protein Kinases / Q000302:isolation & purification* / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012995:Solubility
D000596:Amino Acids; D000906:Antibodies; D000936:Antigen-Antibody Complex; D011494:Protein Kinases