This domain isfound in the C terminus of the bifunctional deaminase-reductase of <taxon tax_id="562">Escherichia coli</taxon>, <taxon tax_id="1423">Bacillus subtilis</taxon> and other bacteria in combination with <db_xref db="INTERPRO" dbkey="IPR002125"/> that catalyses the second and third steps in the biosynthesis of riboflavin, i.e., the deamination of 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate (deaminase) and the subsequent reduction of the ribosyl side chain (reductase) [<cite idref="PUB00006368"/>]. The domain is also present in some HTP reductases from archaea and fungi. Bacterial bifunctional deaminase-reductase, C-terminal