heme

heme
1. The porphyrin chelate of iron in which the iron is Fe(II) (or Fe2+); the oxygen-carrying, color-furnishing, prosthetic group of hemoglobin. 2. Iron complexed with nonporphyrins but related tetrapyrrole structures ( e.g., biliverdin h.). 3. Iron chelated with any porphyrin, irrespective of the valence state of the iron atom. SYN: ferroheme, ferroprotoporphyrin, reduced hematin. [G. haima, blood]
- h. a a derivative of h. found in cytochrome aa3.
- h. c a derivative of h. found in cytochromes c, b4, and f.

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heme or chiefly Brit haem 'hēm n the deep red iron-containing prosthetic group C34H32N4O4Fe of hemoglobin and myoglobin that is a ferrous derivative of protoporphyrin and readily oxidizes to hematin or hemin called also protoheme

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(hēm) 1. any quadridentate chelate of iron with the four pyrrole groups of a porphyrin, further distinguished as ferroheme or ferriheme referring to the chelates of Fe(II) and Fe(III) respectively. The four porphyrin ligands form a square-planar complex; the fifth and sixth coordination positions of the iron atom are perpendicular to the plane of the porphyrin and both may be occupied by strong field ligands, such as a nitrogen atom of a histidine residue of a protein, as in cytochromes, or only one may be so occupied, as in hemoglobin where the sixth position reversibly binds oxygen. 2. ferroheme. 3. protoheme IX, the heme of hemoglobin. See protoheme.

Medical dictionary. 2011.

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  • Hème — de type b Représentation 3D Un hème est un cof …   Wikipédia en Français

  • hème — [ ɛm ] n. m. • 1970; du gr. haima « sang » ♦ Biochim. Pigment contenant du fer ferreux et constituant la partie prosthétique de certaines protéines telles que l hémoglobine. ● hème nom masculin Composé ferreux dérivé de l hématoporphyrine qui… …   Encyclopédie Universelle

  • heme — heme; pro·to·heme; …   English syllables

  • heme — heme. См. гем. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • heme — Síntesis de la partícula demostrativa «he» y el acusativo del pronombre de primera persona. ⇒ He …   Enciclopedia Universal

  • heme —  Heme  Гем   Небелковая часть молекулы гемоглобина. Содержит в молекуле комплекс порфирина с Fe2+. Легко окисляется на воздухе до гематина, имеющего ту же структуру, но содержащего Fe3+. Обусловливает цвет крови, является переносчиком кислорода в …   Толковый англо-русский словарь по нанотехнологии. - М.

  • heme — [hēm] n. [contr. < HEMATIN] the nonprotein, iron containing pigment, C34H32N4O4Fe, that is a component part of hemoglobin, myoglobin, etc …   English World dictionary

  • Heme — A heme (American English) or haem (British English) is a prosthetic group that consists of an iron atom contained in the center of a large heterocyclic organic ring called a porphyrin . Not all porphyrins contain iron, but a substantial fraction… …   Wikipedia

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  • Heme c — Chembox new ImageFile = Heme c.svg ImageSize = 250px IUPACName = OtherNames = Section1 = Chembox Identifiers CASNo = 26598 29 8 PubChem = 444125 SMILES = MeSHName = heme+C Section2 = Chembox Properties Formula = C34H36O4N4S2Fe MolarMass = 684.651 …   Wikipedia

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