Abstract
We cloned and expressed two genes encoding azoreductase homologes, AzrB and AzrC, from Bacillus sp. B29. Purified recombinant AzrB and AzrC were homodimers with 23 kDa identical subunits, and were flavoproteins. NADH was preferred as electron donors for both azoreductases. The azoreductases showed optimal activities at 70 °C (AzrB) and 55 °C (AzrC), and retained activities up to 55 °C (AzrB) and 50 °C (AzrC) after incubation for 1 h. Other enzymatic properties, including the substrate specificities of both azoreductases, were also investigated.
