title: A note on the identity of porcine liver carboxylesterase and prolyl-beta-naphthylamidase.
abstract: Prolyl-beta-naphthylamidase from porcine liver is compared with the two prevalent isoenzymes of pig liver carboxylesterase by isoelectrofocusing experiments and by inhibition studies with phenyl-methyl-sulfonyl fluoride. The results suggest that prolyl-beta-naphthylamidase is identical with the amide-cleaving isoenzyme of carboxylesterase, not with the usually predominant methyl butyrate-hydrolysing isoenzyme. It is questionable whether the recently published sequence of prolyl-beta-naphthylamidase does belong to this enzyme or to the predominant carboxylesterase without amidase activity. Surprisingly, the amide-cleaving carboxylesterase isoenzymes from rat liver have almost no activity with prolyl-beta-naphthylamide.
authors.affiliation: Arbeitsgruppe Gesundheitswissenschaften, Universität Osnabrück, Germany.
authors.forename: E
authors.initials: E
authors.lastname: Heymann
authors.forename: K
authors.initials: K
authors.lastname: Peter
mesh_terms: D015081:2-Naphthylamine / Q000031:analogs & derivatives / Q000378:metabolism; D000595:Amino Acid Sequence; D000626:Aminopeptidases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D000818:Animals; D043182:Carboxylesterase; D002265:Carboxylic Ester Hydrolases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D006868:Hydrolysis; D007526:Isoelectric Point; D007527:Isoenzymes / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D008099:Liver / Q000201:enzymology*; D008969:Molecular Sequence Data; D010664:Phenylmethylsulfonyl Fluoride / Q000737:chemistry; D011392:Proline / Q000031:analogs & derivatives / Q000378:metabolism; D051381:Rats; D013552:Swine
chemical_list: D007527:Isoenzymes; C085530:prolyl-beta-naphthylamide; D010664:Phenylmethylsulfonyl Fluoride; D011392:Proline; D015081:2-Naphthylamine; D002265:Carboxylic Ester Hydrolases; D043182:Carboxylesterase; D000626:Aminopeptidases