Luminescent spectral characteristics of eosin in solutions of human serum albumin when denatured by treatment with sodium dodecyl sulfate

From analysis of the fluorescence spectra of eosin molecules in a solution with human serum albumin (HSA), we have obtained information about the dynamics of protein conformational rearrangements during denaturing of the protein when treated with sodium dodecyl sulfate (SDS) for different pH values of the solution. We hypothesize that HSA denaturing in the presence of SDS occurs in two stages: the first stage is loosening of the protein globules, and the second stage is complete unfolding of the protein molecules. We have shown that denaturating of the protein in the presence of SDS passes through both stages for a solution pH below the isoelectric point of the albumin, while the denaturing stops in the first stage for a solution pH above the isoelectric point of the albumin. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 5, pp. 661–665, September–October, 2006.