Part of the multicomponent anthranilate dioxygenase, that converts anthranilate to catechol. Probably transfers electrons from ferredoxin (AndAb) to NADH. H(+) + NAD(+) + 2 reduced [2Fe-2S]-[ferredoxin] = NADH + 2 oxidized [2Fe-2S]-[ferredoxin] Aromatic compound metabolism; anthranilate degradation via hydroxylation; catechol from anthranilate: step 1/1. Part of a multicomponent enzyme system composed of a reductase (AndAa), a ferredoxin (AndAb) and a two-subunit oxygenase component (AndAc and AndAd). Expression is positively regulated by the transcriptional regulator AndR. Cells lacking this gene are unable to grow on anthranilate. Belongs to the FAD-dependent oxidoreductase family.