Heme Protein

**Semantic type:** Amino Acid, Peptide, or Protein|Biologically Active Substance

**Definition:** Proteins that contain a metal-containing cofactor that consists of an iron atom contained in the center of a large heterocyclic organic ring called a porphyrin. One of the main functions of heme proteins is the retention of molecular oxygen to deliver it for enzymatic reactions. As a result, many heme-containing enzymes are located in the mitochondrion.

**Synonyms:** - Hemeprotein - Hemoprotein