Involved in iodate respiration (PubMed:34215855). May accept electrons from cytochrome c551, and catalyze the reduction of iodate (IO(3)(-)) to produce the chemically unstable intermediate hypoiodous acid (HIO). This intermediate then undergoes abiotic disproportionation to yield two molecules of iodide (I(-)) and one molecule of iodate. The resultant iodate subsequently cycles back into the reductive pathway (PubMed:34215855). The initial reduction of iodate may inadvertently produce low levels of incidental toxic H(2)O(2), which is detoxified by IdrP1 and IdrP2 (PubMed:34215855). Binds 1 [2Fe-2S] cluster per subunit. The iodate reductase (Idr) complex is composed of a molybdopterin-dependent iodate reductase (IdrA and IdrB subunits) and two associated peroxidases (IdrP1 and IdrP2). Predicted to be exported by the Tat system. The position of the signal peptide cleavage has not been experimentally proven. Belongs to the AOX family.