TABLE 5.

Relative activities of the azoreductase from X. azovorans KF46F with different azo dyesa

TABLE 5.
  • a The tests contained in 1 ml 87 μmol of potassium phosphate buffer (pH 7.1), 1 μmol NADH, 25 nmol of the respective azo compounds, and cell extracts (0.15 mg/ml) from E. coli BL21(DE3)pLysSpET-OII-Ex9. The enzyme activities were determined at the absorption maxima of the respective dyes indicated in Table 1. The dyes were added from aqueous or ethanolic (*) stock solutions. The reaction rates are expressed as percentages of that for Orange II (100%). The activities with the dyes added from aqueous stock solutions were related to the activity of the enzyme with Orange II in a purely aqueous system (0.57 U/mg of protein), and those with the dyes from the ethanolic stock solutions with activity for Orange II in the presence of 1% (vol/vol) ethanol (0.14 U/mg of protein) were taken, respectively, as 100% enzyme activity.