Albumin from blood serum of healthy persons and from patients with various pathologies and different severity of diseases was characterized using isoelectric focusing in borate-polyol system. In all the pathologies studied a new component occurred, which had an isoelectric point at pH 5.5 and which was not found in fresh albumin preparations isolated from healthy persons. This fraction was isolated and purified. Its isoelectric point was near pH 4.5-4.6 in isoelectrofocusing with ampholines. The divergences were due to complex formation of albumin with ampholines. The modified protein corresponded immunochemically to the human blood serum albumin, did not contain polymers, had a decreased amount of alpha-helix structures as shown by dispersion of optic rotation and its molecular mass was similar to the mass of native albumin.
Clinical Laboratory Techniques Humans