PURIFICATION AND CHARACTERIZATION OF CATHEPSIN L-LIKE ENZYME FROM THEMUSCLE OF ANCHOVY, ENGRAULIS-JAPONICA

Results relative to inhibitory effects and substrate specificity indic ated that a protease from the muscle of anchovy, Engraulis japonica, w as a cathepsin L-like enzyme. The enzyme was activated by thiol reagen ts and inhibited by thiol-blocking reagents. The molecular weight was estimated to he 25.8 kDa by SDS-PAGE. The enzyme exhibited its maximal activity at FH 6.0 and 50 degrees C for casein and N-benzoyl-D, L-arg inine-beta-naphthylamide. The enzyme hydrolyzed at the position of Phe (1), Asn(3), Val(13), Glu(14), Val(19) and Gly(24) of the insulin beta -chain. The K-m' and k(cat) of the enzyme were 73.4 mu M and 0.5 mu M/ min, respectively, toward 2-Phe-Arg-MNap. (C) 1997 Elsevier Science In c.