Haemoprotein

Part of speech: noun

Definitions

1. Any protein that incorporates a heme group, such as hemoglobin or myoglobin, which allows it to bind oxygen or carry out electron transfer
2. A conjugated protein whose prosthetic group is heme, found in blood, muscle and many enzymes involved in respiration and metabolism
3. A class of iron-containing proteins built around a heme unit, essential for oxygen transport and storage in living organisms

Etymology: Haemoprotein is the British spelling of hemoprotein, a term for a class of proteins that contain a heme group, the iron-bearing ring that lets them bind and carry oxygen or other small molecules. The name is built from the Greek root "haima," meaning blood, combined with "protein," which itself comes from the Greek "prōteios," meaning primary or of first importance. Together the two parts describe a protein that carries a blood-related pigment, such as hemoglobin in red blood cells or cytochromes in mitochondria. The spelling difference comes down to convention. The "ae" form keeps the classical Greek digraph visible, as in "haemorrhage" and "haemoglobin," and it remains standard in British and many Commonwealth scientific writing, while American publications usually drop the "a" to give "hemo-" forms. The two spellings refer to exactly the same molecules, so a reader can treat them as interchangeable.

Synonyms: hemoprotein