Homologous Superfamily

Hemerythrin-like superfamily (IPR035938)

Short name: Hemerythrin-like_sf

Overlapping entries


The haemerythrin family is composed of haemerythrin proteins found in invertebrates, and a broader collection of bacterial and archaeal homologues. Haemerythrin is an oxygen-binding protein found in the vascular system and coelemic fluid, or in muscles (myohaemerythrin) in invertebrates [PMID: 2065779]. Many of the homologous proteins found in prokaryotes are multi-domain proteins with signal-transducing domains such as the GGDEF diguanylate cyclase domain (IPR000160) and methyl-accepting chemotaxis protein (MCP) signalling domain (IPR004089). Most haemerythrins are oxygen-carriers with a bound non-haem iron, but at least one example is a cadmium-binding protein, apparently with a role in sequestering toxic metals rather than in binding oxygen. The prokaryote with the most instances of this domain is Magnetococcus sp. MC-1, a magnetotactic bacterium.

Haemerythrins and myohaemerythrins [PMID: 3681996, PMID: 2362933] are small proteins of about 110 to 129 amino acid residues that bind two iron atoms. They are left-twisted 4-alpha-helical bundles, which provide a hydrophobic pocket where dioxygen binds as a peroxo species, interacting with adjacent aliphatic side chains via van der Waals forces [PMID: 3856224]. In both haemerythrins and myohaemerythrins, the active centre is a binuclear iron complex, bound directly to the protein via 7 amino acid side chains [PMID: 3856224], 5 His, 1 Glu and 1 Asp [PMID: 2065779]. Ovohaemerythrin [PMID: 1425663], a yolk protein from the leech Theromyzon tessulatum seems to belong to this family of proteins, it may play a role in the detoxification of free iron after a blood meal [PMID: 1425663].

Contributing signatures

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