title: Identification of Dipeptidyl-Peptidase (DPP)5 and DPP7 in Porphyromonas endodontalis, Distinct from Those in Porphyromonas gingivalis.
abstract: Dipeptidyl peptidases (DPPs) that liberate dipeptides from the N-terminal end of oligopeptides are crucial for the growth of Porphyromonas species, anaerobic asaccharolytic gram negative rods that utilize amino acids as energy sources. Porphyromonas endodontalis is a causative agent of periapical lesions with acute symptoms and Asp/Glu-specific DPP11 has been solely characterized in this organism. In this study, we identified and characterized two P. endodontalis DPPs, DPP5 and DPP7. Cell-associated DPP activity toward Lys-Ala-4-methylcoumaryl-7-amide (MCA) was prominent in P. endodontalis ATCC 35406 as compared with the Porphyromonas gingivalis strains ATCC 33277, 16-1, HW24D1, ATCC 49417, W83, W50, and HNA99. The level of hydrolysis of Leu-Asp-MCA by DPP11, Gly-Pro-MCA by DPP4, and Met-Leu-MCA was also higher than in the P. gingivalis strains. MER236725 and MER278904 are P. endodontalis proteins belong to the S9- and S46-family peptidases, respectively. Recombinant MER236725 exhibited enzymatic properties including substrate specificity, and salt- and pH-dependence similar to P. gingivalis DPP5 belonging to the S9 family. However, the kcat/Km figure (194 µM-1·sec-1) for the most potent substrate (Lys-Ala-MCA) was 18.4-fold higher as compared to the P. gingivalis entity (10.5 µM-1·sec-1). In addition, P. endodontalis DPP5 mRNA and protein contents were increased several fold as compared with those in P. gingivalis. Recombinant MER278904 preferentially hydrolyzed Met-Leu-MCA and exhibited a substrate specificity similar to P. gingivalis DPP7 belonging to the S46 family. In accord with the deduced molecular mass of 818 amino acids, a 105-kDa band was immunologically detected, indicating that P. endodontalis DPP7 is an exceptionally large molecule in the DPP7/DPP11/S46 peptidase family. The enhancement of four DPP activities was conclusively demonstrated in P. endodontalis, and remarkable Lys-Ala-MCA-hydrolysis was achieved by qualitative and quantitative potentiation of the DPP5 molecule.
authors.affiliation: Department of Oral Molecular Biology, Course of Medical and Dental Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan; Department of Pediatric Dentistry, Course of Medical and Dental Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Haruka
authors.initials: H
authors.lastname: Nishimata
authors.affiliation: Department of Oral Molecular Biology, Course of Medical and Dental Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Ohara-Nemoto
authors.affiliation: Department of Oral Molecular Biology, Course of Medical and Dental Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Tomomi T
authors.initials: TT
authors.lastname: Baba
authors.affiliation: Department of Pediatric Dentistry, Course of Medical and Dental Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Tomonori
authors.initials: T
authors.lastname: Hoshino
authors.affiliation: Department of Pediatric Dentistry, Course of Medical and Dental Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Taku
authors.initials: T
authors.lastname: Fujiwara
authors.affiliation: Division of Molecular Microbiology, Iwate Medical University, Yahaba-cho, Iwate, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Shimoyama
authors.affiliation: Division of Molecular Microbiology, Iwate Medical University, Yahaba-cho, Iwate, Japan.
authors.forename: Shigenobu
authors.initials: S
authors.lastname: Kimura
authors.affiliation: Department of Oral Molecular Biology, Course of Medical and Dental Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Takayuki K
authors.initials: TK
authors.lastname: Nemoto
mesh_terms: D000595:Amino Acid Sequence; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / Q000737:chemistry / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D007527:Isoenzymes / Q000737:chemistry / Q000378:metabolism*; D017861:Porphyromonas / Q000145:classification / Q000201:enzymology*; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity
chemical_list: D007527:Isoenzymes; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases