heme

American  

[heem] / him /

noun

Biochemistry.

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

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heme Scientific  

/ 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 .

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Etymology

Origin of heme

First recorded in 1920–25; shortened form of hematin

Compare meaning

How does heme compare to similar and commonly confused words? Explore the most common comparisons:

• heme vs. hemoglobin

Example Sentences

The team previously designed bacteria that emit light when they encounter heme, but the early versions broke down during digestion and were difficult to retrieve afterward.

From Science Daily

Other human remains found elsewhere in Herculaneum had iron oxide deposits in the skull, suggesting that the fluids in the skull were vaporized by the heat, leaving only traces of degraded heme proteins.

From Salon

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