dipeptidyl peptidase 8

Function

• dipeptidyl peptidase
• cleaves N-terminal dipeptides from proteins having Pro or Ala at position 2
• role in T-cell activation & immune function (putative)
• release of an N-terminal dipeptide, Xaa-Yaa-|-Zaa-, from a polypeptide, preferentially when Yaa is Pro, provided Zaa is neither Pro nor hydroxyproline

Inhibition:

• Zn+2
• serine proteinase inhibitor 4-(2-aminoethyl)benzenesulphonyl fluoride (AEBSF)
• di-isopropylfluorophosphate
• isoindoline derivatives

Kinetic parameters:

• KM=208 uM for Ala-Pro-AMC;
• KM=130 uM for Ala-Pro-AFC;
• KM=120 uM for H-Ala-Pro-pNa;
• KM=1420 uM for H-Ala-Ala-pNa;
• KM=310 uM for H-Arg-Pro-pNa;
• KM=2050 uM for H-Asp-Pro-pNa;
• KM=480 uM for H-Gly-Pro-pNa;
• Optimum pH is 7.4-8.5, little activity below pH 6.5

Compartment

cytoplasm

Alternative splicing

named isoforms=6

Expression

• ubiquitously expressed, highest levels in testis, placenta, prostate, muscle, brain
• induced in activated T-cells

More general terms

• dipeptidyl peptidase (DPP)

Database

• OMIM: https://mirror.omim.org/entry/606819
• UniProt: http://www.uniprot.org/uniprot/Q6V1X1.html