Complete amino acid sequence of the protease inhibitor from buckwheat seeds.

The complete amino acid sequence of protease inhibitor BWI-1 from buckwheat (Fagopyrum esculentum Moench) seeds has been established by automatic Edman degradation and mass spectrometry. The molecule of the inhibitor consists of 69 amino acid residues, with a molecular mass calculated as 7743.8 Da. The active site of the inhibitor contains an Arg45-Asp46 bond. Analysis of the amino acid sequence suggests that the buckwheat seed protease inhibitor is a member of the proteinase inhibitor I family.