<p>The large subunit of [NiFe]-hydrogenase--as well as other nickel metalloenzymes--is synthesized as a precursor devoid of the metalloenzyme active site. This precursor then undergoes a complex post-translational maturation process that requires a number of accessory proteins [<cite idref="PUB00013568"/>, <cite idref="PUB00013569"/>].</p><p>One such group of accessory proteins is represented by <db_xref db="INTERPRO" dbkey="IPR011854"/>, whose members are required for hydrogenase maturation [<cite idref="PUB00013571"/>, <cite idref="PUB00013572"/>] (though their exact function is still unknown). Proteins from this family have similar sequences to <db_xref db="INTERPRO" dbkey="IPR011854"/> members. Thus, members of this family are predicted to play a role in maturation of some nickel metalloenzyme(s). However, other functions can not be ruled out. Both this family and <db_xref db="INTERPRO" dbkey="IPR011854"/> are related to proteins that use both purine derivatives and ATP as substrates. They belong to a superfamily of AIR synthase-related proteins that also includes PurM phosphoribosylaminoimidazole synthetase (AIR synthase, <db_xref db="PIRSF" dbkey="PIRSF001572"/>), thiamine monophosphate kinase (<db_xref db="INTERPRO" dbkey="IPR006283"/>), phosphoribosylformylglycinamidine synthase (FGAM synthase, <db_xref db="PIRSF" dbkey="PIRSF001587"/>), and selenophosphate synthase (selenide, water dikinase).</p> Predicted nickel metalloenzyme maturation factor, AIR synthase-related