Anion-exchange high-performance liquid chromatography of membrane proteins from liver and Morris hepatomas

The separation of proteins from plasma membranes of liver and two Morris hepatomas with different grades of differentiation (Morris hepatomas 7777 and 9121) is described. Size-exclusion high-performance liquid chromatography under non-denaturing conditions provides only poor separation and, with detergent-soluble fractions, unsatisfactory protein recovery. Much better results are obtained by ion-exchange chromatography. The amount of a 175 K protein in the membranes decreased in parallel with the increase in tumour malignancy. This protein appears during ion-exchange chromatography in a broad concentration range, between 0.1 and 0.3 M sodium chloride. Possible explanations for this phenomenon are discussed.