An infrared spectroscopic study on the secondary structure of the black-eyed pea trypsin and chymotrypsin inhibitor--amide I-III and V bands.

The infrared spectrum of native black-eyed pea trypsin and chymotrypsin inhibitor (BTCI) in solid film was measured from 550 to 1750 cm-1 and amide I-III, and V regions have been analyzed. By comparison between the observed bands with the modes calculated for several structures (available in the literature), the occurrence in BTCI of unordered, antipatallel beta-sheet, and beta-turn structures is suggested.