Changes in the protein composition of Epstein-Barr Virus-negative lymphoma cells after EBV-conversion

Two-dimensional protein separation, combining high resolution isoelectric focussing with SDS gel electrophoresis, was applied to analyse Epstein-Barr Virus (EBV)-induced changes in the protein composition of lymphoma cells. Total lysates of the EBV-negative Burkitt lymphoma lines Ramos and BJAB were compared with their permanently converted EBV-genome positive sublines, after 35S-methionine labelling. Five out of seven EBV-infected lines showed a 68k protein, which was absent from both EBV-free parental lines, and was identified as a glycoprotein (gp 68) by metabolic sugar labelling. We conclude that presence of this protein is a direct or indirect consequence of the presence of the EBV genome.