heme

[ heem ]

noun

, Biochemistry.

1. a deep-red iron-containing blood pigment, C 34 H 32 N 4 O 4 Fe, obtained from hemoglobin.

heme

/ hēm /

1. The deep red, nonprotein, iron-containing component of hemoglobin that carries oxygen. Heme is a porphyrin with an iron atom at its center. One of the free valence electrons of the iron atom of heme is bound to the hemoglobin molecule, while the other is available for binding to an oxygen atom. A hemoglobin molecule contains four hemes. Chemical formula: C 34 H 32 FeN 4 O 4 .

Word History and Origins

Origin of heme¹

First recorded in 1920–25; shortened form of hematin

Example Sentences

Heme instantly drew forth a hunting-knife, and cutting Fenwolf's bonds asunder, the latter started to his feet.

From Project Gutenberg