a quinone + H(+) + NADH = a quinol + NAD(+) a quinone + H(+) + NADPH = a quinol + NADP(+) Binds 1 FMN per monomer. Belongs to the WrbA family. Could be the product of a pseudogene. The original protein is interrupted by the insertion of the prophage VT2-Sakai between positions 18 and 19.