Sodium salicylate activates cathepsin B but not cathepsin H from rat spleen.
Effect of sodium salicylate (SA) and its analogues on lysosomal cysteine proteinases, cathepsins B and H, was investigated. Using a sensitive fluorometric assay, SA was shown to activate cathepsin B but not cathepsin H in the presence of cysteine. Kinetics data showed that the SA-stimulated reaction was due to a 4.5-fold decrease in Km. SA caused a decrease in the inactivation rate of cathepsin B by leupeptin and E-64. It was suggested that SA stimulates the activation process of the essential cysteine residue.
D000818:Animals; D001241:Aspirin / Q000494:pharmacology*; D002401:Cathepsin B; D056655:Cathepsin H; D002403:Cathepsins / Q000032:analysis* / Q000037:antagonists & inhibitors; D003546:Cysteine Endopeptidases; D004789:Enzyme Activation / Q000187:drug effects; D007700:Kinetics; D010179:Pancreas / Q000187:drug effects; D051381:Rats; D013154:Spleen / Q000201:enzymology*
D002403:Cathepsins; D003546:Cysteine Endopeptidases; D002401:Cathepsin B; D056655:Cathepsin H; C534128:Ctsh protein, rat; D001241:Aspirin