Comparative study of cytochromes between virus-transformed and untransformed cells

Tissue culture cells of virus-transformed and untransformed cell lines had low contents of cytochromes in the respiratory chain, measured per cell or per mg protein of the cells, in comparison to the cytochrome contents of liver cells in vivo.

In the virus-transformed cells the contents of cytochromes aa₃, b and possibly c₁ were significantly lower than those in the untransformed cells, while the content of cytochrome c was found to be the same or even increased in the transformed cells. Thus, a markedly high ratio of cytochromes c/aa₃ was observed in the transformed cells.

Polarographic measurements of the oxygen uptake have shown a generally low rate of both endogenous respiration and respiration in the presence of glucose and vitamin K₃ in the transformed cells.

The present study indicates that there is a quantitative and possibly qualitative alteration of the respiratory chain components in the transformed cells.