What are the negative allosteric inhibitors?
Negative allosteric effectors (allosteric inhibitors) are substances that bind to the protein (hemoglobin) in a site that is different from the active site and causes lowering of its affinity to O2 meaning that they increase O2 delivery to the tissues by establishing the T configuration which has low affinity to O2. Examples are 2,3-BPG which is more produced by the RBCs in hypoxic conditions to allow enough oxygenation of the tissues even in low O2 tension. Also, acidosis is a condition in which H+ ion (proton) concentration increases, so Hb is more protonated to wash up H+ and at the same time deliver more O2. Same effect can be obtained by increasing CO2. It binds H2O to form H2CO3 (carbonic acid) which dissociates to form HCO3- (bicarbonate ion) and H+ (proton). The protons work as previously mentioned and the bicarbonate ions act as a buffer to minimize the acidosis that can occur from increased protons concentration. This is called the Bohr Effect.
