What is the molecular structure of heme?
What is the molecular structure of heme?
A heme is made from 4 pyrroles, which are small pentagon-shaped molecules made from 4 carbons and 1 nitrogen. Four pyrroles together form a tetrapyrrole. If the tetrapyrrole has substitutions on the side chains which allow it to hold a metal ion, it is called a porphyrin. Thus, a heme is an iron-holding porphyrin.
What are some characteristics of heme?
The two defining features of all heme proteins are the iron metal center and the tetrapyrrole macrocycle that comprise the protein active site. While the iron center is the site of catalytic activities for heme proteins, the structure of the prosthetic group in charge of holding onto the metal is also very important.
What is heme protein structure?
A hemeprotein (or haemprotein; also hemoprotein or haemoprotein), or heme protein, is a protein that contains a heme prosthetic group. The heme consists of iron cation bound at the center of the conjugate base of the porphyrin, as well as other ligands attached to the “axial sites” of the iron.
What is the structure of hemoglobin?
Hemoglobin has a quaternary structure. It consists of two pairs of different proteins, designated the α and β chains. There are 141 and 146 amino acids in the α and β chains of hemoglobin, respectively. As in myoglobin, each subunit is linked covalently to a molecule of heme.
What is the molecular weight of one heme unit?
Heme b
| PubChem CID | 4973 |
|---|---|
| Molecular Formula | C34H32FeN4O4 |
| Synonyms | heme heme b protoheme Haem protoheme IX More… |
| Molecular Weight | 616.5 |
| Parent Compound | CID 4971 (Protoporphyrin IX) |
What is the chemical name for heme?
C34H32FeN4O4
Heme | C34H32FeN4O4 – PubChem.
How is heme produced?
Heme is largely synthesized in erythroid cells for incorporation into hemoglobin, which consists of four heme proteins. The kidneys produce a hormone called erythropoietin that stimulates the production of heme in the bone marrow.
What is the function of heme groups?
The Heme group gives myoglobin and hemoglobin the ability to bind oxygen because of the presence of iron atom. It also contributes to the red color found in muscles and blood. Each heme group contains an iron atom that is able to bind to one oxygen (O2) molecule.
What exactly is heme?
Heme is composed of a ringlike organic compound known as a porphyrin, to which an iron atom is attached. It is the iron atom that reversibly binds oxygen as the blood travels between the lungs and the tissues.
Is heme an enzyme?
Heme enzymes can catalyze both reductive and oxidative chemistry but here we focus on those that catalyze oxidation reactions, and especially those for which crystal structures are available.
What does heme mean?
Medical Definition of heme. : the deep red iron-containing prosthetic group C 34H 32N 4O 4Fe of hemoglobin and myoglobin that is a ferrous derivative of protoporphyrin and readily oxidizes to hematin or hemin .
What is heme in hemoglobin?
heme(Noun) The component of hemoglobin responsible for binding oxygen, consists of an iron ion that binds oxygen and a porphyrin ring that binds the globin molecules; one molecule binds one molecule of oxygen.
Is heme a protein?
A hemeprotein (or haemprotein; also hemoprotein or haemoprotein), or heme protein, is a protein that contains a heme prosthetic group. They are a large class of metalloproteins. The heme group confers functionality, which can include oxygen carrying, oxygen reduction, electron transfer, and other processes.
What is the chemistry of hemoglobin?
In molecules, hemoglobin, molecular formula: C2932H4724N828O840S8Fe4, is an oxygen-transport metalloprotein, comprised of carbon, hydrogen, nitrogen, oxygen, sulfur, and iron, found in the red blood cells of all vertebrates; it was first analyzed in 1959.