Isolation and Characteristics of Carboxypeptidase B from Zebra Blenny (Salaria basilisca) Viscera

AbstractCarboxypeptidase B (CPB) from zebra blenny (Salaria basilisca) viscera was purified using ammonium sulphate precipitation and Sephadex G-100 gel filtration, with a 28-fold increase in specific activity and 21.72% recovery. The molecular weight of the enzyme was estimated to be 34.5 kDa by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The optimum pH and temperature for the enzyme activity were around pH 8.0 and 60°C, respectively, using Hippuryl-l-Arg as a substrate. The enzyme was unstable above 50°C and below pH 5.0. The enzyme was activated by Co2+ and Zn2+ and inhibited by ethylenediaminetetraacetic acid (EDTA). The N-terminal amino acid sequence of the enzyme was determined as S P S Y T K Y N T. The CPB kinetic constants, Km and kcat for Hippuryl-l-Arg, were 0.32 mM and 36.23 s−1, respectively.Keywordszebra blenny (S. basilisca)carboxypeptidase Bpurificationcharacterization