Characteristics of an aminopeptidase from Japanese cedar (Cryptomeria japonica) pollen.
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.
Nagata
Hiroyuki
H
Department of Biomedical Engineering, Toin University of Yokohama, Toin Human Science and Technology Center, Japan.
Takei
Tsutomu
T
Kojima
Ryoko
R
Kodera
Yoh
Y
Nishimura
Hiroyuki
H
Inada
Yuji
Y
Matsushima
Ayako
A
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
D004791:Enzyme Inhibitors; D010446:Peptide Fragments; D004492:Edetic Acid; D000626:Aminopeptidases