His-Xaa-Ser system putative quinone modification maturase
One clue for the interpretation of this protein family is homology to the MauG protein (see TIGR03791) involved in the tryptophan tryptophylquinone post-translational modification of methylamine dehydrogenase light (beta) chain. The other is occurrence only in a five gene context in which two members are radical SAM proteins (TIGR03977 and TIGR03978) also likely involved in post-translational modification.
Jiyao W et al.(2023). "The conserved domain database in 2023.",