The ribosomes of the Novikoff tumor cells: isolation, general properties and electrophoretic analysis of the protein moiety.

The ribosomes from Novikoff tumor and rat liver cells were extracted, purified and analyzed. The isolated ribosomes are active in Poly-U directed Poly-Phe synthesis. Sucrose density gradient centrifugation showed that the Novikoff tumor cells contained, in contrast to liver cells, almost no polysomes. The ribosomal proteins from the ribosomes were extracted and subsequently analyzed by gel electrophoresis. No differences between the ribosomal proteins of the normal and neoplastic cells could be detected by one-dimensional sodium dodecyl sulfate gel electrophoresis. Two-dimensional urea gel electrophoresis showed great similarities between the ribosomal proteins of the two kinds of cells. However some differences could be detected.