Purification and partial characterisation of trypsin inhibitors from seeds of Clitoria ternatea

Three trypsin inhibitors of 20, 12 and 7 kDa were isolated in pure form from seeds of the vine Clitoria ternatea L of the tribe Glycineae of the Papilionoideae. The 20‐kDa inhibitor is a one‐chain molecule with arginine in the reactive site. The 12‐kDa one is also a one‐chain molecule and has lysine in the reactive site. It is also an inhibitor of chymotrypsin. They were tentatively assigned to the Kunitz and Bowman‐Birk families, respectively. The small molecular weight inhibitor (7 kDa) also has an arginine in the reactive site and is probably of the Bowman‐Birk type.