In proliferating and tumor cells the lactate produced does not only derive from the conversion of glucose. Part of the lactate is also produced by the degradation of the amino acid glutamine.
The conversion of the amino acid glutamine to lactate has been termed – in anology to glycolysis – as glutaminolysis.
Glutaminolysis contains parts of the citrate cycle and the malate-
The reaction steps of glutaminolysis take place in the cytosol and mitochondria.
Glutaminolysis is an energy producing pathway.
In contrast to glycolytic energy production, glutaminolytic energy production depends on oxygen supply.
All tumor cells are characterized by high glutaminolytic flux rates.