<p>This protein has been characterised in <taxon tax_id="1423">Bacillus subtilis</taxon> [<cite idref="PUB00016396"/>] as the iron-sulphur cluster binding-subunit of xanthine dehydrogenase (pucE), acting in conjunction with pucC, the FAD-binding subunit and pucD, the molybdopterin binding subunit. The more common XDH complex (<db_xref db="GENPROP" dbkey="GenProp0640"/>) includes the xdhA gene as the Fe-S cluster binding component.</p>