FIG. 3.

Effects of temperature on flavin reductase stability. After purified enzyme was preincubated at different temperatures for 30 min, enzyme reactions were carried out as described in Materials and Methods. The total reaction volume was 0.5 ml, and 0.55 μg of purified enzyme from the wild-type strain was added to each reaction mixture. The enzyme activity was determined by measuring the decrease in absorbance at 340 nm.