Question

In what manner does 2,3-bisphosphoglycerate (2,3-BPG) interact with the beta chains on hemoglobin (Hb)?

a) It binds to the iron center of Hb
b) It binds to the heme group of Hb
c) It interacts with the amino acid residues in the Hb chains
d) It attaches to the oxygen molecules carried by Hb

Answer 1

2,3-bisphosphoglycerate (2,3-BPG) interacts with the beta chains on hemoglobin (Hb) by binding to the positively charged amino acid residues, stabilizing the low-affinity state and promoting oxygen release.

Step-by-step explanation:

2,3-bisphosphoglycerate (2,3-BPG) interacts with hemoglobin (Hb) by binding to specific sites on the beta chains of the hemoglobin molecule. Specifically, 2,3-BPG binds in the central cavity of the hemoglobin tetramer and interacts with positively charged amino acid residues of the beta chains. This binding, which forms a salt bridge with the amino terminal of the beta chains, stabilizes the hemoglobin in its low-affinity state for oxygen (deoxyhemoglobin), facilitating the release of oxygen to the tissues. 2,3-BPG does not bind directly to the iron center, the heme group, or the oxygen molecules.