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Carboxypeptidase B was purified from the pyloric ceca of the starfish Asterias amurensis. The final enzyme preparation was nearly homogeneous in polyacrylamide gel electrophoresis and its molecular weight was estimated as approximately 34 000. The optimum pH and temperature of the enzyme for hydrolysis of benzoyl-glycyl-l-arginine were at approximately pH 7.5 and 55 °C, respectively. The enzyme was unstable at above 50 °C and at below pH 5.0. The enzyme was activated by Co2+, but was inhibited by EDTA and Hg2+. The N-terminal amino acid sequence of A. amurensis carboxypeptidase B was ASFDYNVYHSYQEIMNWITN. [ABSTRACT FROM AUTHOR]

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 Nα-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 Ca2+. The N-terminal amino acid sequence of A. pectinifera trypsin, IVGGHEF, was found. [Copyright &y& Elsevier]