The MopB_DMSOR-BSOR-TMAOR CD contains dimethylsulfoxide reductase (DMSOR), biotin sulfoxide reductase (BSOR), trimethylamine N-oxide reductase (TMAOR) and other related proteins. DMSOR always catalyzes the reduction of DMSO to dimethylsulfide, but its cellular location and oligomerization state are organism-dependent. For example, in Rhodobacter sphaeriodes and Rhodobacter capsulatus, it is an 82-kDa monomeric soluble protein found in the periplasmic space; in E. coli, it is membrane-bound and exists as a heterotrimer. BSOR catalyzes the reduction of biotin sulfixode to biotin, and is unique among Mo enzymes because no additional auxiliary proteins or cofactors are required. TMAOR is similar to DMSOR, but its only natural substrate is TMAO.This CD is of the conserved molybdopterin_binding C-terminal (MopB_CT) region present in many, but not all, MopB homologs.
Jiyao W et al.(2023). "The conserved domain database in 2023.",