Dimer-tetramer transition in hemoglobins from Liophis miliaris—II. Evidence with the stripped proteins

Abstract

1. 1. Whole Liophis miliaris hemolysate stored under refrigeration at pH 7 becomes progressively deoxygenated and presents two hemoglobin forms of mol. wts 32,500 and 64,000, consistent with oxydimers and deoxytetramers respectively. 2. 2. The Hill plot determined at pH 6.5 considering oxygen pressure capable to saturate up to 50% of the hemoglobin shows a coefficient value of n H = 2.06, whereas that found at higher oxygen pressure was n H = 0.85. 3. 3. The apparent Bohr effect of about ΔH + = −0.4 in the stripped hemoglobin was explained by the increase of co-operative deoxytetramer T-state/non-co-operative ratio as a function of proton concentration.