Fig. 3: Structural characterization of HbG-Makassar in its R2-state (a, b) and T-state (c, d).
a, c Simulated annealing composite omit maps (2Fo-Fc) are contoured to 1.0 σ for the heme cofactor in the HbG-Makassar tetramer. Heme cofactor is shown as red sticks and the composite omit map is shown as blue mesh. The presence (a) and absence (c) of the electron density for the water molecule coordinated to the heme iron suggest the protein is in its relaxed and tense states, respectively. b, d Ribbon representation of superimposed structures of HbG-Makassar and HbA in its R2 (b; HbA PDB id: 1BBB) and T state (d; HbA PDB id:2DN2). The α and β protomers are shown in teal and purple for HbG-Makassar and gray for HbA, respectively. Hemes are shown as red sticks and the βE6A substitution found in HbG-Makassar is shown as light purple spheres.
