title: Influence of urea on the high-performance cation-exchange chromatography of hen egg white lysozyme.
abstract: The effects of urea on the high-performance cation-exchange chromatography of hen egg lysozyme are reported. The capacity factor, k', has been determined as a function of cation concentration with a polyaspartate column using the acetates of Na+, K+, Ca2+ and Mg2+. Urea decreases lysozyme retention. Plots of log k' vs. log ionic strength show linear relationships. The slope of the plot describing the Ca2+ elution of lysozyme was the same in the presence of 5 M urea as in its absence. In strong urea solutions and at elevated temperatures, lysozyme denaturation is evidenced by a marked decrease in k'. The temperature range for denaturation corresponded closely to that observed in intrinsic fluorescence and circular dichroism measurements. The potential utility and limitations of high-performance ion-exchange chromatography for studying protein denaturation are discussed.
mesh_terms: D000818:Animals; D002412:Cations; D002645:Chickens; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D002852:Chromatography, Ion Exchange / Q000379:methods; D004529:Egg White; D005260:Female; D009113:Muramidase / Q000302:isolation & purification*; D011487:Protein Conformation; D011489:Protein Denaturation; D014508:Urea
chemical_list: D002412:Cations; D014508:Urea; D009113:Muramidase