ISOLATION AND CHARACTERIZATION OF 5 SERINE PROTEASES WITH TRYPSIN-LIKE, CHYMOTRYPSIN-LIKE AND ELASTASE-LIKE CHARACTERISTICS FROM THE GUT OF THE LUGWORM ARENICOLA-MARINA (L) (POLYCHAETA)

Five proteases were isolated from the digestive fluid of the lugworm, Arenicola marina L. The enzymes (molecular weight 24.0-24.6 kDa) were classified as serine proteases. Three enzymes showed a cleavage specificity corresponding to mammalian trypsin (E.C. 3.4.21.4). One protease possessed a chymotrypsin-like cleavage pattern (E.C. 3.4.21.1), and the fifth preferred cleavage behind short-chain amino acids like an elastase (E.C. 3.4.21.36). Detailed investigations revealed differences in molecular characteristics and cleavage patterns compared to mammalian proteases, especially in the chymotrypsin- and the elastase-like enzymes.