bacterial SoxC is a member of the sulfite oxidase (SO) family of molybdopterin binding domains. SoxC is involved in oxidation of sulfur compounds during chemolithothrophic growth. Together with SoxD, a small c-type heme containing subunit, it forms a hetrotetrameric sulfite dehydrogenase. This molybdopterin cofactor (Moco) binding domain is found in a variety of oxidoreductases, main members of this family are nitrate reductase (NR) and sulfite oxidase (SO). Common features of all known members of this family are that they contain one single pterin cofactor and part of the coordination of the metal (Mo) is a cysteine ligand of the protein and that they catalyze the transfer of an oxygen to or from a lone pair of electrons on the substrate.
Jiyao W et al.(2023). "The conserved domain database in 2023.",