Evaluation of Inhibitory Activity, Purification and X-Ray Crystallography of Alpha—Amylase Inhibitor from Phaseolus Vulgaris Cultivars of Uttarakhand

Abstract The present work is based on analysis of inhibitory activity of alpha-amylase inhibitor in selected cultivars of Phaseolus vulgaris of Uttarakhand. Fifteen samples were assessed for inhibitory activity of alpha-amylase inhibitor. Significant variations were found in different cultivars. Crude extract of alpha-amylase inhibitor from sample PUR (Purola) have shown maximum inhibitory activity (70.2 ± 0.84). Crude extract of all the cultivars have shown considerable variations in inhibitory activity in the temperature ranging from 20ºC to 100ºC. Based on inhibitory activity and heat stability profile, the alpha amylase inhibitor was purified from PUR cultivar. The purified inhibitor was found to be stable even at 90ºC with an inhibitory activity of 97.20 ±0.09. The molecular weight of purified inhibitor on Native PAGE (Polyacrylamide gel electrophoresis) was found to be 31kd, consisting of two subunits of 17kd and 14kd on SDS-PAGE.

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Activity changes in cranberry bean (Phaseolus vulgaris) .ALPHA.-amylase inhibitor by chemical modification and enzymatic digestion.

Journal of Nutritional Science and Vitaminology ◽

10.3177/jnsv.35.71 ◽

1989 ◽

Vol 35 (1) ◽

pp. 71-80 ◽

Cited By ~ 5

Author(s):

Makoto KOTARU ◽

Hung-Yu YEH ◽

Hideki YOSHIKAWA ◽

Tsuneo IKEUCHI ◽

Kimikazu IWAMI ◽

...

Keyword(s):

Phaseolus Vulgaris ◽

Chemical Modification ◽

Enzymatic Digestion ◽

Alpha Amylase ◽

Amylase Inhibitor ◽

Alpha Amylase Inhibitor

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PURIFICATION AND PARTIAL CHARACTERIZATION OF A GLYCOPROTEIN ALPHA-AMYLASE INHIBITOR FROM WHITE KIDNEY BEAN (PHASEOLUS VULGARIS. L)

Journal of Food Biochemistry ◽

10.1111/j.1745-4514.2007.00147.x ◽

2008 ◽

Vol 32 (1) ◽

pp. 72-84 ◽

Cited By ~ 9

Author(s):

M.Y. YANG ◽

X.Q. ZHANG ◽

Y. MA ◽

J. SHEN ◽

J.R. SONG ◽

...

Keyword(s):

Phaseolus Vulgaris ◽

Kidney Bean ◽

Alpha Amylase ◽

Partial Characterization ◽

Phaseolus Vulgaris L ◽

Amylase Inhibitor ◽

Alpha Amylase Inhibitor

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Mutants of common bean alpha-amylase inhibitor-2 as an approach to investigate binding specificity to alpha-amylases

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x2004000300001 ◽

2004 ◽

Vol 39 (3) ◽

pp. 201-208 ◽

Cited By ~ 7

Author(s):

Maria Cristina Mattar da Silva ◽

Luciane Vieira Mello ◽

Marise Ventura Coutinho ◽

Daniel John Rigden ◽

Goran Neshich ◽

...

Keyword(s):

Phaseolus Vulgaris ◽

Inhibitory Activity ◽

Molecular Basis ◽

Tobacco Plants ◽

Defense Proteins ◽

Amylase Inhibitor ◽

Terminal Loop ◽

Stored Grains ◽

Alpha Amylase Inhibitor ◽

Amylase Inhibitors

Despite the presence of a family of defense proteins, Phaseolus vulgaris can be attacked by bruchid insects resulting in serious damage to stored grains. The two distinct active forms of a-amylase inhibitors, a-AI1 and a-AI2, in P. vulgaris show different specificity toward a-amylases. Zabrotes subfasciatus a-amylase is inhibited by a-AI2 but not by a-AI1. In contrast, porcine a-amylase is inhibited by a-AI1 but not by a-AI2. The objective of this work was to understand the molecular basis of the specificity of two inhibitors in P. vulgaris (a-AI1 and a-AI2) in relation to a-amylases. Mutants of a-AI2 were made and expressed in tobacco plants. The results showed that all the a-AI2 mutant inhibitors lost their activity against the insect a-amylases but none exhibited activity toward the mammalian a-amylase. The replacement of His33 of a-AI2 with the a-AI1-like sequence Ser-Tyr-Asn abolished inhibition of Z. subfasciatus a-amylase. From structural modeling, the conclusion is that the size and complexity of the amylase-inhibitor interface explain why mutation of the N-terminal loop and resultant abolition of Z. subfasciatus a-amylase inhibition are not accompanied by gain of inhibitory activity against porcine a-amylase.

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