Experiments with beta-chain variants of the hemoglobin of Mus musculus.

Starch gel electrophoretic and ultracentrifuge methods failed to demonstrate any differences between the hemoglobins of mice of the Shanghai and HBBP/Cag strains and crosses among these strains. The apparent identity of these hemoglobins is thought to stem from the contribution of Asian mice to the British mouse fancy from which the laboratory strains have Hbb-p in part descend. Maleate buffer of pH 7 or above can be used to prevent the formation of disulfide-bridged dimers of mouse hemoblobins. However, the minor electrophoretic bands of Hbb-p and Hbb-d react with approximately twice as much maleate as the major bands of each of these hemoglobins, although the minor bands like the major contain only one free cysteine group per beta chain. This can be explained by the alkylation of the epsilon-amino of lysine residue beta76, but some evidence for the alkylation of histidine in the minor band of Hbb-p is also presented.