This protein contains 4 porphyrin rings surrounding 4 atoms of iron.
The SNO residue on the beta-93 cysteine of this protein helps transfer nitric oxide to the cell membrane. One conformation of this protein is stabilized by an ion pair between His-146 and Asp-94 as well as ion pairs formed by carbamates formed from this protein's N-terminal residues. A version of this protein containing tightly-packed gamma subunits is known as its "fetal" type. When hydrogen ions react with this protein, it is converted from the "relaxed" state to the "tense" state in the (*) Bohr effect. 2,3-bisphosphoglycerate lowers the affinity of this tetrameric protein, which is the classic example of cooperative binding. This protein contains 4 porphyrin rings surrounding 4 atoms of iron. For 10 points, sickle-cell anemia occurs due to a mutation in what protein that transports oxygen in the blood?
The SNO residue on the beta-93 cysteine of this protein helps transfer nitric oxide to the cell membrane.
hemoglobin [or Hb]