Primary structure of Kunitz-type trypsin inhibitor-2a (pI 5.9) from Psophocarpus tetragonolobus (L.) DC seed.

A A Kortt, J E Burns, J B Caldwell, T Ferro, P M Strike

CSIRO, Division of Biomolecular Engineering, Parkville Laboratory, Victoria, Australia.

Journal of protein chemistry 1991 Apr

filter terms:

The primary structure of acidic trypsin inhibitor-2a (WBTI-2a, pI 5.9) from Psophocarpus tetragonolobus (L.) DC seed was determined. This inhibitor consists of a single polypeptide chain of 180 amino acids including four half-cystine residues and has an N-terminal residue of pyroglutamic acid. The sequence of WBTI-2a, pI 5.9, showed 84% identity to acidic trypsin inhibitor-2 (WBTI-2, pI 5.1) but only 57% identity to the basic trypsin inhibitor (WBTI-1, pI 8.9) and 50% identity to the chymotrypsin inhibitor of winged bean. The data indicate that winged bean seed contains a family of three Kunitz-type inhibitors which have about 50% identity.

Citation

A A Kortt, J E Burns, J B Caldwell, T Ferro, P M Strike. Primary structure of Kunitz-type trypsin inhibitor-2a (pI 5.9) from Psophocarpus tetragonolobus (L.) DC seed. Journal of protein chemistry. 1991 Apr;10(2):183-8