RESUMO
A comparison was made of ultra-violet fluorescence characteristics of albumin enriched protein fractions of serum blood of 35 glomerulonephritis (GN) patients, 30 uremic haemodialysis patients, and 40 donors. It has been found that fluorescence spectra of the albumin enriched fractions of serum from GN patients are blue shifted as compared with those of donors' serum preparations. At the same time fluorescence spectra of the albumin enriched fractions of donors' serum are similar, while those of GN patients vary significantly. The ratio of fluorescence intensities at 320 and 365 nm (A = I320/I365), characterizing the spectrum position is 1.27 +/- 0.05, for protein preparations of donors, while that for GN patients varies within the limits of 1.3-2.1. Fluorescence spectra of protein fractions from blood serum of uremic patients are red shifted (A = 0.77-1.29) in comparison with those of donors' blood. Chromatographic investigations show that protein preparations of GN patients' blood contain monomers and dimers of albumin, that can be divided according to their molecular masses or hydrophobic properties of the surface. Joint chromatographic and spectral analysis allowed to distinguish up to six albumin enriched fractions. A protein fraction with blue fluorescence spectrum was obtained by gel-filtration and ion exchange chromatography. A higher concentration of this fraction determines a high value of parameter A, that is typical for protein preparations of GN patients' blood. Amino acid sequence shows that one component of this fraction is beta-haptoglobin.