title: N-alpha-Tosyl-L-lysine chloromethyl ketone and N-alpha-tosyl-L-phenylalanine chloromethyl ketone inhibit protein kinase C.
abstract: TLCK (N-alpha-tosyl-L-lysine chloromethyl ketone) inhibits protein kinase C whether or not the enzyme is under the regulation of Ca2+ and phospholipid. TLCK (IC50 = 1 mM) is a much more potent inhibitor of protein kinase C than TPCK (N-alpha-tosyl-L-phenylalanine chloromethyl ketone) (IC50 = 8 mM), suggesting that the lysyl moiety of TLCK may be specifically recognized by the active site of protein kinase C. These results extend the evidence that the active site of protein kinase C recognizes basic amino acids, and suggest that the active sites of protein kinase C and the cAMP-dependent protein kinase, which is also inhibited by TLCK and TPCK, are structurally related.
mesh_terms: D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology*; D000818:Animals; D001665:Binding Sites; D001921:Brain / Q000201:enzymology; D002118:Calcium / Q000502:physiology; D010743:Phospholipids / Q000502:physiology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors*; D051381:Rats; D013329:Structure-Activity Relationship; D014107:Tosyllysine Chloromethyl Ketone / Q000494:pharmacology*; D014108:Tosylphenylalanyl Chloromethyl Ketone / Q000494:pharmacology*
chemical_list: D000590:Amino Acid Chloromethyl Ketones; D010743:Phospholipids; D014107:Tosyllysine Chloromethyl Ketone; D014108:Tosylphenylalanyl Chloromethyl Ketone; D011493:Protein Kinase C; D002118:Calcium