Molecular basis of hemoglobin adaptation in the high-flying bar-headed goose
Fig 5
Compensatory interaction between spatially proximal α-chain residues in bar-headed goose Hb.
The mutation Aα63V produces a >2-fold increase in autoxidation rate (kauto; ± 1 SEM) on genetic backgrounds with the ancestral Gly at residue position α18. This effect is fully compensated by Gα18S, as indicated by two double-mutant cycles (A and B) in which mutations at both sites are tested individually and in pairwise combination.