NADH:quinone oxidoreductase/Mrp antiporter, membrane subunit (IPR001750)

Short name: ND/Mrp_mem

Overlapping homologous superfamilies


Domain relationships



This domain is found in subunits NuoL/ND5, NuoM/ND4, and NuoN/ND2 of the NADH:quinone oxidoreductase (complex I), Mrp antiporters subunits A and D, and in membrane subunits of hydrogenase complexes, such as hydrogenase-4 and F420H2 dehydrogenase.

Mrp-type antiporters comprise the cation/proton antiporter family 3 (CPA3), commonly referred to as Mrp. They are the products of operons that carry either six or seven genes (mrpA-G), and form complexes containing all subunits [PMID: 15980940, PMID: 18408029]. They have Na(+)/H(+) antiporter activity [PMID: 24142251]. Two of the Mrp proteins, MrpA and MrpD, resemble NuoL/ND5, NuoM/ND4, NuoN/ND2, the homologous subunits that constitute the membrane-embedded, proton-translocating core of complex I [PMID: 12914915, PMID: 20826797, PMID: 12460669, PMID: 20595580]. They also resemble subunits of membrane-bound hydrogenases, such as HyfB, HyfD and HyfF from E.coli [PMID: 9387241] and F420H2 dehydrogenasa (FPO complex) subunits L, N and M [PMID: 10751389].

Contributing signatures

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