Nature of the tryptic/chymotryptic inhibitor from horsegram (Dolichos biflorus).
Sarma, P. R. and Rao, D. R. (1991) Nature of the tryptic/chymotryptic inhibitor from horsegram (Dolichos biflorus). Indian Journal of Biochemistry & Biophysics, 28 (5-6). pp. 418-24. ISSN 0301-1208
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Abstract
A protease inhibitor specific to trypsin and chymotrypsin was purified from horsegram (Dolichos biflorus) with the inhibition index 0.24 micrograms/micrograms for trypsin and 0.36 micrograms/micrograms for chymotrypsin. In SDS-PAGE, the inhibitor protein was seen as a single band with apparent molecular mass Mr = 15,500. However, on fast protein liquid chromatography (FPLC) or non-denaturating PAGE, the inhibitor resolved into four components revealing the existence of isoinhibitors. Data on amino acid analysis indicate that the isoinhibitors are closely related. The major amino acids in the inhibitor are half cystine (18.9 mole %), aspartic acid (12.7 mole %) and serine (14.3 mole %). The inhibitor was partially stable to 0.1% sodium dodecyl sulphate, 8M urea or 6M guanidine hydrochloride. The inhibitory activity was lost on reduction or carboxamidomethylation or acetylation. Modification of the arginine groups or CNBr cleavage of the protein did not result in significant loss of either tryptic or chymotryptic inhibitory activities. The isoinhibitors separated by FPLC reacted with polyclonal antibody raised in rabbits and had pI values ranging from 4.8-5.1. The horsegram inhibitor thus resembles other Bowman-Birk protease inhibitors.
Item Type: | Article |
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Uncontrolled Keywords: | horsegram, dolichos biflorus, trypsin, chymotrypsin |
Subjects: | 600 Technology > 08 Food technology > 16 Nutritive value > 05 Enzymes 600 Technology > 08 Food technology > 22 Legumes-Pulses |
Divisions: | Dept. of Biochemistry |
Depositing User: | Food Sci. & Technol. Information Services |
Date Deposited: | 15 Nov 2021 04:50 |
Last Modified: | 01 Jun 2022 11:05 |
URI: | http://ir.cftri.res.in/id/eprint/2323 |
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