COMPARISON OF TRYPSIN AND CHYMOTRYPSIN FROM THE VISCERA OF ANCHOVY, ENGRAULIS-JAPONICA

The molecular weights of trypsin and chymotrypsin purified from anchovy viscera were estimated to be 25.6 and 26.1 Kda, respectively, by SDS-PAGE, Both enzymes had their maximal activity at pH 9.0 and 45 degrees C for casein and at pH 8.0 and 45 degrees C for synthetic substrates. Trypsin hydrolyzed at the position of Arg(22) and Lys(29), and chymotrypsin did at the position of Phe(1), Tyr(16), Phe(24), Phe(25) and Tyr(26) of insulin beta-chain. The K-m' and k(cat) of trypsin were 50 mu M and 1.84 mu M min(-1) toward N-benzoyl-L-arginine-p-nitroanilide (BAPNA) and those of chymotrypsin were 89 mu M and 10.0 mu M(-1)min(-1) toward N-succinyl-(Ala)(2)-Pro-Phe-p-nitroanilide. The activation energy of trypsin and chymotrypsin were estimated to be 14 Kcal/mol toward N-benzoyl-L-arginine-p-nitroanilide and 6.5 Kcal/mol toward benzoyl-L-tyrosine ethyl ester.