home *** CD-ROM | disk | FTP | other *** search
- ***************************************************
- * Prolyl oligopeptidase family serine active site *
- ***************************************************
-
- The prolyl oligopeptidase family [1,2,3] consist of a number of evolutionary
- related peptidases whose catalytic activity seems to be provided by a charge
- relay system similar to that of the trypsin family of serine proteases, but
- which evolved by independent convergent evolution. The known members of this
- family are listed below.
-
- - Prolyl endopeptidase (EC 3.4.21.26) (PE) (also called post-proline cleaving
- enzyme). PE is an enzyme that cleaves peptide bonds on the C-terminal side
- of prolyl residues. The sequence of PE has been obtained from a mammalian
- species (pig) and from a bacteria (Flavobacterium meningosepticum); there
- is a high degree of sequence conservation between both sequences.
- - Escherichia coli protease II (EC 3.4.21.83) (oligopeptidase B) (gene prtB)
- which cleaves peptide bonds on the C-terminal side of lysyl and argininyl
- residues.
- - Dipeptidyl peptidase IV (EC 3.4.14.5) (DPP IV). DPP IV is an enzyme that
- removes N-terminal dipeptides sequentially from polypeptides having
- unsubstituted N-termini provided that the penultimate residue is proline.
- - Yeast vacuolar dipeptidyl aminopeptidase A (DPAP A) (gene: STE13) which is
- responsible for the proteolytic maturation of the alpha-factor precursor.
- - Yeast vacuolar dipeptidyl aminopeptidase B (DPAP B) (gene: DAP2).
- - Acylamino-acid-releasing enzyme (EC 3.4.19.1) (acyl-peptide hydrolase).
- This enzyme catalyzes the hydrolysis of the amino-terminal peptide bond of
- an N-acetylated protein to generate a N-acetylated amino acid and a protein
- with a free amino-terminus.
-
- A conserved serine residue has experimentally been shown (in E.coli protease
- II as well as in pig and bacterial PE) to be necessary for the catalytic
- mechanism. This serine, which is part of the catalytic triad (Ser, His, Asp),
- is generally located about 150 residues away from the C-terminal extremity of
- these enzymes (which are all proteins that contains about 700 to 800 amino
- acids).
-
- -Consensus pattern: D-x(3)-A-x(3)-[LIVMFYW]-x(14)-G-x-S-x-G-G-[LIVMFYW](2)
- [S is the active site residue]
- -Sequences known to belong to this class detected by the pattern: ALL, except
- for yeast DPAP A.
- -Other sequence(s) detected in SWISS-PROT: NONE.
-
- -Last update: June 1994 / Text revised.
-
- [ 1] Rawlings N.D., Polgar L., Barrett A.J.
- Biochem. J. 279:907-911(1991).
- [ 2] Barrett A.J., Rawlings N.D.
- Biol. Chem. Hoppe-Seyler 373:353-360(1992).
- [ 3] Polgar L., Szabo E.
- Biol. Chem. Hoppe-Seyler 373:361-366(1992).
-