title: Characterization of Aplysia carboxypeptidase E.
abstract: Carboxypeptidase E (CPE) is involved in the biosynthesis of peptide hormones and neurotransmitters. To determine whether a recently reported Aplysia californica cDNA encodes a CPE-like enzyme, this cDNA was expressed in the baculovirus system. The Aplysia CPE is optimal at pH 5.5-6.5 and is inhibited by chelating agents and by the sulfhydryl reagent p-chloromercuriphenyl sulfonate. The effect of divalent cations and active site-directed inhibitors on enzyme activity are generally similar for Aplysia and rat CPE. Western blot analysis using antisera to the N- and C-terminal regions of the Aplysia CPE show that the Aplysia CPE is present in atrial glands and ovotestis. This Aplysia CPE is purified on a p-aminobenzoyl-Arg Sepharose affinity column under conditions that selectively purify rat CPE. Taken together, these results suggest that the previously cloned cDNA represents a CPE-like enzyme that is expressed in Aplysia tissue.
authors.affiliation: Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
authors.forename: S
authors.initials: S
authors.lastname: Juvvadi
authors.forename: X
authors.initials: X
authors.lastname: Fan
authors.forename: G T
authors.initials: GT
authors.lastname: Nagle
authors.forename: L D
authors.initials: LD
authors.lastname: Fricker
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001048:Aplysia / Q000201:enzymology*; D016367:Baculoviridae / Q000235:genetics; D015153:Blotting, Western; D043423:Carboxypeptidase H; D002268:Carboxypeptidases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D002413:Cations, Divalent / Q000494:pharmacology; D018076:DNA, Complementary; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015870:Gene Expression; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000276:immunology / Q000494:pharmacology; D051381:Rats; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism
chemical_list: D002413:Cations, Divalent; D018076:DNA, Complementary; D004791:Enzyme Inhibitors; D010446:Peptide Fragments; D011994:Recombinant Proteins; D002268:Carboxypeptidases; D043423:Carboxypeptidase H