TRYPSIN INHIBITORY ACTIVITY OF A POLYPEPTIDE ISOLATED FROM RED KIDNEY BEANS, THAT ALSO ENHANCES LYMPHOCYTE STIMULATION

A polypeptide isolated from red kidney beans, Phaseolus vulgaris, which has previously been shown to stimulate RNA synthesis in cultures of mouse spleen lymphocytes and plasmolyzed E. coli, is here shown to be a potent inhibitor of trypsin and α-chymotrypsin. This polypeptide is compared with commercially available trypsin inhibitors with regard to their capacity to inhibit some proteolytic enzymes and to stimulate in vitro cultures of lymphocytes. Similar to FV the lima been trypsin inhibitor was found to possess a stimulating effect on the RNA as well as the DNA synthesis in lymphocyte cultures. © 1979.