Inhibitors of human and bovine trypsin and chymotrypsin in fenugreek (Trigonella foenum-graecum L.) seeds. Reactive sites and C-terminal sequences.
The reactive sites and the C-terminal sequences of three trypsin chymotrypsin inhibitors from fenugreek seeds (TFI-B2, TFI-N2, and TFI-A8) were determined by chemical modification and carboxypeptidase degradation of native und enzymatically modified inhibitors. TFI-B2 contained lysine and leucine in the trypsin- and chymotrypsin-reactive sites, respectively, and -(Lys)-Phe-Leu-Ile was the C-terminal sequence. TFI-N2 possessed arginine and leucine in the trypsin- and chymotrypsin-reactive sites, respectively, and -(Tyr)-Lys-Ile-Leu at the C-terminus. TFI-A8 contained two arginines, one in each of the two reactive sites. At least one of these sites, although mainly directed against trypsin, could also bind some chymotrypsin. -(Leu)-Phe-Ile-Arg was found to be the C-terminus in TFI-A8. These results confirmed that all three fenugreek inhibitors belong to the Bowman-Birk proteinase inhibitor family.
Weder
J K
JK
Institut für Lebensmittelchemie, Technische Universität München, Garching, Federal Republic of Germany.
Haussner
K
K
D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D002918:Chymotrypsin / Q000037:antagonists & inhibitors*; D006801:Humans; D008969:Molecular Sequence Data; D012639:Seeds / Q000737:chemistry*; D014361:Trypsin Inhibitors / Q000737:chemistry*
D014361:Trypsin Inhibitors; D002918:Chymotrypsin