What is the primary function of 2, 3-diphosphoglycerate (DPG) in adult hemoglobin?

2,3-Diphosphoglycerate (DPG) plays a crucial role in the regulation of oxygen release from adult hemoglobin. Its primary function is to facilitate oxygen release to the tissues.

When DPG binds to hemoglobin, it stabilizes the T (tense) state of the hemoglobin molecule, which has a lower affinity for oxygen compared to the R (relaxed) state. This interaction promotes the release of oxygen from hemoglobin into the tissues that need it, especially in areas that have lower oxygen levels. The presence of DPG is particularly important under conditions of high metabolic activity, where tissues consume more oxygen.

The relevance of DPG in this process is highlighted in situations where tissues are actively respiring or during conditions such as chronic hypoxia, where DPG levels may increase, further enhancing oxygen release to meet metabolic demands. Thus, the function of DPG is directly linked to how efficiently hemoglobin can deliver oxygen throughout the body.