Isolation and characteristics of trypsin from pyloric ceca of the starfish Asterina pectinifera

Abstract

Trypsin was purified from pyloric ceca of the starfish Asterina Pectinifera by ammonium sulfate precipitation, gel filtration, and cation-exchange chromatography. Final enzyme preparation was nearly homogeneous in sodium dodecyl sulfate-polyacrylamide gel electrophoresis and its molecular weight was estimated as approximately 28 000. Optimum pH and temperature of A. pectinifera trypsin for hydrolysis of N α- p-Tosyl- l-arginine methyl ester hydrochloride were approximately pH 8.0 and 55 °C, respectively. A. pectinifera trypsin was unstable at above 50 °C and below pH 5.0, and was not activated by adding Ca 2+. The N-terminal amino acid sequence of A. pectinifera trypsin, IVGGHEF, was found.