New active analogues of Cucurbita maxima trypsin inhibitor III (CMTI-III) modified in the non-contact region.
Four new analogues of trypsin inhibitor CMTI-III(3-28) = [desArg1,desVal2,desGly29]CMTI-III which was recently shown to be fully active, were synthesized by the solid-phase method. The introduction of glycine in position 9 (peptide 1) and Gly-Pro-Gly (peptide 2) and Gly-Pro-Asn (peptide 3) in the regions 17-19 and 23-25, respectively, did not change the antitrypsin activity of all modified peptides. All of these substitutions are presumed to be outside the trypsin-binding loop as judged from the X-ray structure of the complex between beta-trypsin and the related inhibitor CMTI-I. Also the fourth analogue which was substituted in all the positions mentioned, exhibited the full activity.
Rózycki
J
J
Faculty of Chemistry, University of Gdańsk, Poland.
Kupryszewski
G
G
Rolka
K
K
Ragnarsson
U
U
Zbyryt
T
T
Krokoszyńska
I
I
Wilusz
T
T
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002417:Cattle; D018360:Crystallography, X-Ray; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism; D014357:Trypsin / Q000378:metabolism; D014361:Trypsin Inhibitors / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism
D000596:Amino Acids; C081870:CMTI protein, Cucurbita maxima; D010940:Plant Proteins; D014361:Trypsin Inhibitors; D014357:Trypsin