Cytochrome c-552/DMSO reductase-like, haem-binding domain (IPR019020)

Short name: Cyt-c552/DMSO_Rdtase_haem-bd

Overlapping homologous superfamilies


Domain relationships



This entry represents a haem-binding domain found in cytochromes b558/566 (subunit A), c-551 and c-552, as well as in members of the type-II members of the microbial dimethyl sulphoxide (DMSO) reductase family.

The DMSO reductase family is a large and rapidly expanding group of enzymes found in bacteria and archaea that share a common form of molybdenum cofactor known as bis(molybdopterin guanine dinucleotide)Mo [PMID: 15311335]. In addition to the molybdopterin subunit, these enzymes also contain an iron-sulphur subunit. These include two distinct but very closely related periplasmic proteins of anaerobic respiration: selenate reductase and chlorate reductase [PMID: 15866716]. Other proteins containing this subunit include dimethyl sulphide dehydrogenase and ethylbenzene dehydrogenase [PMID: 11294876, PMID: 12067345, PMID: 16030201].

One member of the DMSO reductase family is eythylbenzene dehydrogenase, which is a heterotrimer of three subunits that catalyses the anaerobic degradation of hydrocarbons (alpha, beta and gamma subunits). This entry matches the gamma subunit, whose structure is known [PMID: 16962969]. The alpha subunit contains the catalytic centre as a Molybdenum cofactor-complex. This removes an electron-pair from the hydrocarbon and passes it along an electron transport system involving iron-sulphur complexes held in the beta subunit and a Haem b molecule contained in the gamma subunit. The electron-pair is then subsequently passed to an as yet unknown receiver. The enzyme is found in a variety of different bacteria.

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0020037 heme binding

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.