Demonstration and isolation of the hybrid hemoglobins alpha 2 A beta A beta C and alpha 2 A beta S beta C

The corss-linking reagent p,p'-difluoro-m,m'-dinitrodiphenylsulfone has been used to fix in the tetramer form the various species of hemoglobin present in mixtures of hemoglobin A and hemoglobin C and of hemoglobin S and hemoglobin C. Following reaction, the presence of the hybrid hemoglobins alpha 2 A beta A beta C and alpha 2 A beta S beta C in these hemoglobin mixtures was demonstrated electrophoretically and the hybrids were isolated by ion-exchange chromatography. The identity of the alpha 2 A beta A beta C hybrid was further verified by peptide analysis. The success in cross-linking alpha 2 A beta 2 C, alpha 2 A beta A beta C, and alpha 2 A beta S beta C with p,p'-difluoro-m,m'-dinitrodiphenylsulfone shows that the distance between the alpha chain amino terminals in solution for these hemoglobin species is the same as in normal hemoglobin.