Identification of novel peptide inhibitors for human trypsins.
Human trypsin isoenzymes share extensive sequence similarity, but certain differences in their activity and susceptibility to inhibitors have been observed. Using phage display technology, we identified seven different peptides that bind to and inhibit the activity of trypsin-3, a minor trypsin isoform expressed in pancreas and brain. All of the peptides contain at least two of the amino acids tryptophan, alanine and arginine, whereas proline was found closer to the N-terminus in all but one peptide. All peptides contain two or more cysteines, suggesting a cyclic structure. However, we were able to make synthetic linear variants of these peptides without losing bioactivity. Alanine replacement experiments for one of the peptides suggest that the IPXXWFR motif is important for activity. By molecular modeling the same amino acids were found to interact with trypsin-3. The peptides also inhibit trypsin-1, but only weakly, if at all, trypsin-2 and -C. As trypsin is a highly active enzyme which can activate protease-activated receptors and enzymes that participate in proteolytic cascades involved in tumor invasion and metastasis, these peptides might be useful lead molecules for the development of drugs for diseases associated with increased trypsin activity.
Department of Clinical Chemistry, P.O. Box 63, University of Helsinki and Helsinki University Central Hospital, FIN-00014 University of Helsinki, Helsinki, Finland.
Ping
P
Wu
Department of Biosciences and Biocenter Kuopio, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio, Finland.
Janne
J
Weisell
Department of Biosciences and Biocenter Kuopio, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio, Finland.
Miikka
M
Pakkala
Department of Biosciences and Biocenter Kuopio, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio, Finland.
Mikael
M
Peräkylä
Department of Clinical Chemistry, P.O. Box 63, University of Helsinki and Helsinki University Central Hospital, FIN-00014 University of Helsinki, Helsinki, Finland.
Lei
L
Zhu
Department of Clinical Chemistry, P.O. Box 63, University of Helsinki and Helsinki University Central Hospital, FIN-00014 University of Helsinki, Helsinki, Finland.
Riitta
R
Koistinen
The David H. Koch Center, University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.
Erkki
E
Koivunen
Department of Clinical Chemistry, P.O. Box 63, University of Helsinki and Helsinki University Central Hospital, FIN-00014 University of Helsinki, Helsinki, Finland.
Ulf-Håkan
UH
Stenman
Department of Biosciences and Biocenter Kuopio, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio, Finland.
Ale
A
Närvänen
Department of Clinical Chemistry, P.O. Box 63, University of Helsinki and Helsinki University Central Hospital, FIN-00014 University of Helsinki, Helsinki, Finland.
Hannu
H
Koistinen
D001665:Binding Sites / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008958:Models, Molecular; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000494:pharmacology*; D013329:Structure-Activity Relationship; D014357:Trypsin / Q000378:metabolism*; D014361:Trypsin Inhibitors / Q000737:chemistry / Q000235:genetics / Q000494:pharmacology*; D014362:Trypsinogen / Q000037:antagonists & inhibitors / Q000378:metabolism
D011993:Recombinant Fusion Proteins; D014361:Trypsin Inhibitors; C064831:PRSS2 protein, human; D014362:Trypsinogen; C489303:PRSS1 protein, human; C040749:PRSS3 protein, human; D014357:Trypsin