Hämerythrin
| Hämerythrin ( Dendrostomum dyscritum ) | ||
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| Model of the hemerythrin monomer from peanut worm ( Dendrostomum dyscritum ) according to PDB 1HMO | ||
| Mass / length primary structure | 113 amino acids | |
| Secondary to quaternary structure | Homooctamer | |
| Cofactor | iron | |
| Identifier | ||
| External IDs | ||
| Occurrence | ||
| Parent taxon | Invertebrates | |
Hämerythrins are respiratory blood proteins that function as oxygen transporters in a number of marine invertebrates (e.g. annelids , syringes , arm pods ) . So they perform the same tasks as hemoglobin and myoglobin in higher animals. There are no known tribes of animals living on land that have haemythrin.
Despite their name, the haemerythrins do not belong to the heme enzymes. The active center of the reduced state is represented by two iron (II) ions bridged by a hydroxide ligand and two carboxylates . The coordination spheres of the iron centers are completed by two or three histidine ligands. In the course of binding the dioxygen molecule, it simply oxidizes both iron centers and is itself reduced to the peroxide ion. At the same time, it takes over a proton from the hydroxido bridge. The hydroperoxide ion formed is then bound to the five-coordinate iron center and to the bridging oxo function with a hydrogen bond. The color of the oxidized molecule is purple, when deoxidized it is colorless; the molecular mass is 108 kDa .
See also
- Iron metabolism
- Hemocyanin , a similar copper-containing protein with a corresponding function.
swell
Individual evidence
- ↑ InterPro entry
- ↑ R. Sauermost (ed.): Dictionary of Biology on CD-Rom . Spektrum Akademischer Verlag, Munich 2004, ISBN 3-8274-0356-1 .
- ^ R. Wehner , W. Gehring : Zoologie . 24th edition. Georg Thieme Verlag, Stuttgart, New York 2007, ISBN 978-3-13-367424-9 , pp. 339 (Table 4.4).