HEME

Heme

A haem or heme is a chemical compound of a type known as a prosthetic group consisting of an Fe2+ ion contained in the centre of a large heterocyclic organic ring called a porphyrin, made up of four pyrrolic groups joined together by methine bridges. Not all porphyrins contain iron, but a substantial fraction of porphyrin-containing metalloproteins have heme as their prosthetic group; these are known as hemoproteins. Hemes are most commonly recognized in their presence as components of hemoglobin, the red pigment in blood, but they are also components of a number of other hemo-proteins such as myoglobin, cytochrome, endothelial nitric ...

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heme

Noun

  1. The component of hemoglobin (and other hemoproteins) responsible for binding oxygen, consists of an iron ion that binds oxygen and a porphyrin ring that binds the globin molecules; one molecule binds one molecule of oxygen.


The above text is a snippet from Wiktionary: heme
and as such is available under the Creative Commons Attribution/Share-Alike License.

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