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

Precision fermentation is not a new technique in the plant-based world: Impossible Foods brews plant-derived heme to make its fake meat bleed.

From Salon

The company’s burgers also contain a genetically modified plant-based version of heme, an iron-containing molecule that is a component of beef.

From Los Angeles Times

The vegan diet promoted more red blood cell-linked pathways, including those involved in heme metabolism, which could be due to the higher iron content of this diet.

From Science Daily

Hemoglobin binds gases such as oxygen, carbon dioxide, and nitric oxide, and it is an iron carrier via the heme complex.

From Science Daily

Willett notes that the heme iron in red meat may have some impact on the pancreas itself, which is where insulin is developed.

From Salon