Alteration of the α1β2/α2β1 subunit interface contributes to the increased hemoglobin-oxygen affinity of high-altitude deer mice
The α subunit is shown in the cartoon, and the key residues are represented as a stick model. The residues unique to highland and lowland hemoglobin are labeled in cyan and pink, respectively. The highland hemoglobin α1 subunit is colored in cyan, and its β2 subunit is colored in gray. Both subunits from the lowland hemoglobin are colored in pink. The right side boxes indicate differences in the α1β2/α2β1 interface coordinates, particularly the β2His 97 imidazole ring orientation relative to the α1 residues.