| Abstract: | A trypsin inhibitor, isolated from whole-wheat grain (Triticum aestivum L.) by the method of bio-specific chromatography on trypsin-Sepharose, was potent in inhibiting human salivary alpha-amylase. The bi-functional alpha-amylase/trypsin inhibitor was characterized by a narrow specificity for other alpha-amylases and proteinases. The high thermostability of the inhibitor was lost in the presence of SH group-reducing agents. The inhibitor-trypsin complex retained its activity against alpha-amylase. The inhibitor-alpha-amylase complex was active against trypsin. Studies of the enzyme kinetics demonstrated that the inhibition of alpha-amylase and trypsin was noncompetitive. Our results suggest the existence of two independent active sites responsible for the interaction with the enzymes. |
