COMPLETE AMINO-ACID-SEQUENCES OF 2 TRYPSIN-INHIBITORS FROM BUCKWHEAT SEED

The major trypsin isoinhibitors from seed extracts of buckwheat (Fagop yrum esculentum Monch) were purified by affinity chromatography, anion exchange chromatography, anion exchange HPLC and reversed-phase HPLC, and the complete amino acid sequences of two isoinhibitors, BTI-1 and BTI-2, were established by automated Edman degradation. Each isoinhib itor consists of a single polypeptide chain of 69 amino acids, includi ng two Cys residues. The N-terminal sequence of a third isoform, BTI-3 , was also determined. The buckwheat trypsin isoinhibitors exhibit cle ar sequence similarities with the potato chymotrypsin inhibitor I fami ly of serine proteinase inhibitors. Copyright (C) 1996 Elsevier Scienc e Ltd.