title: Characteristics of an aminopeptidase from Japanese cedar (Cryptomeria japonica) pollen.
abstract: A peptidase from Japanese cedar pollen, Jc-peptidase, was clarified to preferentially hydrolyze an MCA substrate of Phe-MCA (L-phenylalanyl-4-methylcoumaryl-7-amide). This study examined substrate specificities of Jc-peptidase using oligopeptides. Jc-peptidase hydrolyzed Phe-Phe and Tyr-Phe effectively and hydrolyzed Leu-Phe, Met-Phe, and Arg-Phe moderately. Other substrates such as Ala-Phe, Asp-Phe, and Pro-Phe were not hydrolyzed with the peptidase. Results obtained with a series of aminoacyl-Phe peptides were compatible with the facts obtained for MCA substrates except for Arg-MCA. Effects of amino acid residues in the P1' position were also examined using Phe-amino acids. An N-terminal phenylalanine residue was actually released from bioactive peptides such as molluscan cardioexcitatory neuropeptide (FMRF-NH(2)). Because the activity was inhibited with Zn(2+) and EDTA, Jc-peptidase was inferred to belong to the metalloproteases. The N-terminal amino acid sequence was determined to be APIGVQLEIEENYVHMYNGF and an internal sequence to be EIFAATFNVDEETEA, but no homology with other proteins was found.
authors.affiliation: Department of Biomedical Engineering, Toin University of Yokohama, Toin Human Science and Technology Center, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nagata
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Takei
authors.forename: Ryoko
authors.initials: R
authors.lastname: Kojima
authors.forename: Yoh
authors.initials: Y
authors.lastname: Kodera
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nishimura
authors.forename: Yuji
authors.initials: Y
authors.lastname: Inada
authors.forename: Ayako
authors.initials: A
authors.lastname: Matsushima
mesh_terms: D000595:Amino Acid Sequence; D000626:Aminopeptidases / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D032485:Cryptomeria / Q000201:enzymology*; D004492:Edetic Acid / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006868:Hydrolysis; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry; D011058:Pollen / Q000201:enzymology*; D013379:Substrate Specificity
chemical_list: D004791:Enzyme Inhibitors; D010446:Peptide Fragments; D004492:Edetic Acid; D000626:Aminopeptidases