Xaa. It does not act on peptides with N-terminal Glu, Asn or Gln, nor does it cleave isoaspartyl peptides
Reaction: Dipeptidase E catalyses the hydrolysis of dipeptides AspXaa. It does not act on peptides with N-terminal Glu, Asn or Gln, nor does it cleave isoaspartyl peptides
Other names: aspartyl dipeptidase; peptidase E; PepE gene product (Salmonella typhimurium)
Comments: A free carboxy group is not absolutely required in the substrate since Asp-Phe-NH2 and Asp-Phe-OMe are hydrolysed somewhat more slowly than dipeptides with free C-termini. No peptide larger than a C-blocked dipeptide is known to be a substrate. Asp-NH-Np is hydrolysed and is a convenient substrate for routine assay. The enzyme is most active near pH 7.0, and is not inhibited by di-isopropylfluorophosphate or phenylmethanesulfonyl fluoride. Belongs In peptidase family S51.
Links to other databases: BRENDA, EXPASY, KEGG, MEROPS, Metacyc, PDB, CAS registry number:
References
1. Håkansson, K., Wang, A.H.J. and Miller, C.G. The structure of aspartyl dipeptidase reveals a unique fold with a Ser-His-Glu catalytic triad. Proc. Natl. Acad. Sci. USA 97 (2000) 14097-14102. [PMID: 11106384]
2. Lassy, R.A.L. and Miller, C.G. Peptidase E, a peptidase specific for N-terminal aspartic dipeptides, is a serine hydrolase. J. Bacteriol. 182 (2000) 2536-2543. [PMID: 10762256]