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Trypsin PC from the hepatopancreas of the king crab Paralithodes camtschatica was isolated and purified to apparent homogeneity by ion-exchange chromatography on Aminosilochrom and DEAE-Sephadex and affinity chromatography on arginine-agarose. The yield of the enzyme was 37.7%, and the purification degree was 21. Trypsin PC has a molecular mass of 29 kDa and pI < 2.5. It hydrolysis N-benzoyl-L-arginine p-nitroanilide at the optimum pH of 7.5-8.0 and at the temperature optimum of 55 degrees C (K(m) = 0.05 mM). Trypsin PC retained its activity within the pH range of 5.8-9.0 in the presence of Ca2+. The enzyme was inhibited by the specific inhibitors of serine proteases diisopropyl fluorophoshate and phenylmethylsulfonyl fluoride, by the trypsin inhibitor N-tosyl-L-lysylchloromethylketone, and by the trypsin inhibitors from soybean and potato. Trypsin PC was found to hydrolyze amide bonds formed by carboxylic groups of lysine and arginine in peptide substrates. The N-terminal sequence of this enzyme is IVGGTEVTPG.

Different proteins are revealed in cell wall of yeast cells Candida utilis by means of specific proteolysis with subtilisins TV and 72, trypsin and purified collagenase of Clostridium histolyticum. Some of them were characterized by resistance to trypsin and sensitivity to subtilisin TV. In young cells this group is represented essentially by a protein of 33 kD, which appears to be one of the structural proteins, binding fibrillae of carbohydrate. Other proteins proved to be sensitive to both trypsin and subtilisin. Among these proteins a protein with mol. mass 80 kD was revealed; its sensitivity to extremely specific hydrolysis by bacterial collagenase suggests it to contain amino acid sequences characteristic for collagens of higher eukaryotes.