Question

What effects might you expect in a mammal whose hemoglobin is mutated such that it lacks a Bohr effect? Be sure to provide a full explanation of these consequences.

Answer 1

Ans) Oxygen binding affinity of hemoglobin is inversely proportional to H⁺ ions (Higher the H+ ions,lower the pH). Thus, if H⁺ ion increases (or in low pH) ,oxygen binding affinity of hemoglobin will decrease and thus more PO₂ (Partial pressure of oxygen) will be required for given % oxygen saturation of hemoglobin. This effect of pH on oxygen binding affinity of hemoglobin is referred to as Bohr effect.

If hemoglobin gets mutated such that it lacks a Bohr effect then, more PO₂ will not be required and thus, all the four sites of hemoglobin will be occupied by oxygen molecules, which will result in high oxygen requirement by the body which can lead to hypoxemia also (abnormally low level of oxygen in the blood) if PO₂ is less than 80mm Hg.