Autor: |
Bjelke, Jais R., Christensen, Jesper, Nielsen, Per F., Branner, Sven, Kanstrup, Anders B., Wagtmann, Nicolai, Rasmussen, Hanne B. |
Zdroj: |
Biochemical Journal; June 2006, Vol. 396 Issue: 2 p391-399, 9p |
Abstrakt: |
Dipeptidyl peptidases 8 and 9 have been identified as gene members of the S9b family of dipeptidyl peptidases. In the present paper, we report the characterization of recombinant dipeptidyl peptidases 8 and 9 using the baculovirus expression system. We have found that only the full-length variants of the two proteins can be expressed as active peptidases, which are 882 and 892 amino acids in length for dipeptidyl peptidase 8 and 9 respectively. We show further that the purified proteins are active dimers and that they show similar Michaelis–Menten kinetics and substrate specificity. Both cleave the peptide hormones glucagon-like peptide-1, glucagon-like peptide-2, neuropeptide Y and peptide YY with marked kinetic differences compared with dipeptidyl peptidase IV. Inhibition of dipeptidyl peptidases IV, 8 and 9 using the well-known dipeptidyl peptidase IV inhibitor valine pyrrolidide resulted in similar Ki values, indicating that this inhibitor is non-selective for any of the three dipeptidyl peptidases. |
Databáze: |
Supplemental Index |
Externí odkaz: |
|