The effect of ethidium bromide on the membrane glycopeptides in control and virus-transformed cells.

Glycopeptides derived from surface and subcellular membranes of control (BHK2,/C13) and virus-transformed (CIS/B1) baby hamster kidney cells treated or untreated with ethidium bromide were studied. Ethidium bromide was found to mimic virus transformation with regard to the alteration of the glycopeptide patterns observed upon Sephadex G-50 chromatography. Elution profiles of glycopeptides obtained from virus-transformed cells demonstrated the existence of both a normal component (Peak B) and an enrichment of material eluting as a higher molecular weight component (Peak A). Material eluting in the Peak A region is greatly enhanced in both the control and virus-transformed cells after treatment with ethidium bromide. This alteration of the glycopeptide pattern was observed with glycopeptides derived from surface, endoplasmic reticular and mitochondrial membranes. Mitochondrial glycopeptides obtained from ethidium bromide-treated cells also seem to contain an increased amount of material eluting as a component of lower molecular weight than Peak B. This material, designated Peak C, may be located in the intramembrane space of the mitochondrion.