Metabolism of Ascites Tumor Cells. Iv. Enzymatic Reactions Involved in Adenosinetriphosphate Degradation Induced by 2-deoxyglucose.

The changes in cellular nucleotides accompanying the phosphorylation of 2-deoxyglucose by respiring Krebs ascites tumor cells have been studied. The degradation of ATP by dephosphorylation and deamination to form ADP, AMP, IMP, and inosine in 2-deoxyglucose-treated cells was followed chromatographically and electrophoretically. A rise in cellular AMP concentration, a rise and subsequent fall in cellular IMP, and a steady rise in inosine until it was the predominant 250to 260-m/uabsorb ing compound in the reaction mixture were observed when ascites cells were treated with 2-deoxy glucose. GTP was also broken down in 2-deoxyglucose-treated cells, and one of its breakdown products GDP was identified. A pathway is proposed for the 2-deoxyglucose-induced ATP degradation ha these cells. Hexokinase, adenylate kinase, adenylic deaminase, and 5'-nucleotidase, the