<p>FO synthase catalyzes the radical-mediated transfer of the hydroxybenzyl group from 4-hydroxyphenylpyruvate (HPP) to 5-amino-6-ribitylamino-2,4(1H,3H)-pyrimidinedione to form 7,8-didemethyl-8-hydroxy-5-deazariboflavin (FO) [<cite idref="PUB00045884"/>]. This entry represents CofH/subunit 2 of FO synthase, it binds 1 4Fe-4S cluster, which is coordinated with 3 cysteines and an exchangeable S-adenosyl-L-methionine.Although this entry contains CofH/subunit2 of coenzyme F(420) biosynthesis it appears to hit genomes more broadly than just the subset that make coenzyme F(420), so that narrower group is being built as a separate family (<db_xref db="INTERPRO" dbkey="IPR019940"/>).</p>