Purification of a 29‐kDa hemocyte proteinase of Sarcophaga peregrina

Publisher Website
Google Scholar
Abstract
Previously, we suggested the participation of a hemocyte proteinase in the dissociation of fat body of Sarcophaga peregrina (flesh fly) at metamorphosis. We have now purified this proteinase to near homogeneity from pupal hemocytes. It is a cysteine proteinase with a molecular mass of 29 kDa and has a unique substrate specificity hydrolyzing both Suc‐Leu‐Leu‐Val‐Tyr‐MCA and Z‐Phe‐Arg‐MCA (Suc, succinyl; MCA, methylcoumaryl‐7‐amide; Z, carbobenzoxy), which are substrates for chymotrypsin and cathepsin B, respectively. Partial similarity was found between the amino‐terminal sequence of this proteinase and that of catepsin B, including Pro, Glu and Arg residues conserved in the papain superfamily of enzymes.