Illustration of the role of glutathione in the inhibition of sickle hemoglobin polymerization: Two hemoglobin tetramers are shown in the surface representation and helical cartoon, wherein α and β globin chains are coloured magenta and cyan, respectively. The proximity of covalently bound glutathione to βCys93, represented as stick model, to the residues of the groove region is shown in yellow in the inset. βVal6 of the adjacent tetramer, the key residue in the polymerisation, is shown in spacefill model. Image kindly provided by Amit Kumar Mandal.