[Role of beta-cyanoalanine hydratase in the synthesis of asparagine in white lupine].

A highly active beta-cyanoalanine hydratase catalyzing the asparagine synthesis from beta-cyanoalanine was isolated from 11-day-old etyolated seedlings of white lupine (Lupinus albus) and subjected to purification. In white lupine seedlings the enzyme activity is 300 times as high as that in extracts of blue lupine (Lupinus angustifolius). The experimental data suggest that in white lupine seedlings asparagine synthesis from cysteine and cyanide occurs via beta-cyanoalanine production with its subsequent hydratation.

[Artifactual multiple forms of beta-cyanoalanine synthase from white lupine].

The three active forms of beta-cyanoalanine synthase (EC 4.4.1.

[Beta-cyanoalanine synthase from white lupin: some catalytic properties].

Highly purified beta-cyanoalanine synthase was prepared from 11-day-old etiolated sprouts of white lupine in the presence of diisopropylfluorophosphate. The enzyme preparations were homogeneous during polyacrylamide gel electrophoresis; their specific activity exceeded that of the blue lupine enzyme 100-fold. The purification procedure included preparation of mitochondrial acetonated powder, isolation of enzyme, chromatography on DEAE-Sephadex A-50, fractionation on Sephadex G-100 and preparative polyacrylamide gel electrophoresis.