Erythrocruorin

Erythrocruorin

Erythrocruorin, Lumbricus terrestris

Erythrocruorin is an oxygen-transporting protein complex of many annelids and arthropods that is counted among the globins . By assembling several hundred subunits, it has a molar mass of several million Daltons . Chlorocruorin acts as a prosthetic group . Erythrocruorin is not packaged in cells, but is found both in the blood and in the coelom of the animal. It has a higher O ₂ - affinity than similar proteins of other organisms (eg. Hemoglobin ). As a result, the animals are able to tolerate hypoxic conditions , as they often form in their habitats ( sediments , intertidal zones ).

An example is the erythrocruorin of the rope worm ( Lumbricus terrestris ), which is made up of twelve heterododecamers of the globin subunits A, B, C and D (= 144) and 36 connecting proteins.

further reading

• Royer WE, Strand K, van Heel M, Hendrickson WA: Structural hierarchy in erythrocruorin, the giant respiratory assemblage of annelids . In: Proc. Natl. Acad. Sci. USA . 97, No. 13, June 2000, pp. 7107-11. PMID 10860978 . PMC 16507 (free full text).
• Ilan E, Weisselberg E, Daniel E: Erythrocruorin from the water-flea Daphnia magna. Quaternary structure and arrangement of subunits . In: Biochem. J. . 207, No. 2, November 1982, pp. 297-303. PMID 7159384 . PMC 1153860 (free full text).

Individual evidence

1. ↑ InterPro: Erythrocruorin
2. ↑ Strand K, Knapp JE, Bhyravbhatla B, Royer WE: Crystal structure of the hemoglobin dodecamer from Lumbricus erythrocruorin: allosteric core of giant annelid respiratory complexes . In: J. Mol. Biol. . 344, No. 1, November 2004, pp. 119-34. doi : 10.1016 / j.jmb.2004.08.094 . PMID 15504406 .