Double-headed trypsin/chymotrypsin inhibitors from horse gram (Dolichos biflorus): purification, molecular and kinetic properties.

Sreerama, Y. N. and Das, J. R. and Rao, D. R. and Gowda, L. R. (1997) Double-headed trypsin/chymotrypsin inhibitors from horse gram (Dolichos biflorus): purification, molecular and kinetic properties. Journal of Food Biochemistry, 21 (6). pp. 461-477.

PDF Journal_of_Food_Biochemistry_21(1)_1997_461-477.pdf Restricted to Registered users only Download (790kB)

Abstract

Four proteinase inhibitors were purified to homogeneity from horse gram (Dolichos biflorus). These inhibitors are double-headed and inhibit trypsin and chymotrypsin simultaneously and independently. Dissociation constants range between 0.87 and 4.6 x 10-7M. Each of the 6 isoinhibitors possesses a crucial lysine residue at the trypsin reactive site. These inhibitors have molecular masses of 8.5 kDa and isoelectric points of 4.6-5.6. They exist mainly as dimers under physiological conditions. Amino acid analysis revealed high levels of half-cystine, serine, aspartate and proline but low levels of methionine and aromatic amino acids. Amino-terminal sequence analysis revealed that each of the 4 isoinhibitors has a conserved core sequence but all are divergent at the N-terminal end. These inhibitors belong to the Bowman-Birk (BBI) family of proteinase inhibitors as reflected by their inhibitory properties, amino acid composition and homology to other BBI.

Item Type:	Article
Uncontrolled Keywords:	ENZYME-INHIBITORS; LEGUMES-; HORSE-GRAM; PROTEINASES-INHIBITORS
Subjects:	600 Technology > 08 Food technology > 16 Nutritive value > 03 Proteins 600 Technology > 08 Food technology > 22 Legumes-Pulses
Divisions:	Dept. of Biochemistry
Depositing User:	Food Sci. & Technol. Information Services
Date Deposited:	09 Aug 2008 05:15
Last Modified:	01 Jul 2015 11:43
URI:	http://ir.cftri.res.in/id/eprint/7786

Actions (login required)

View Item