Relation between 2-Deoxyglucose Phosphorylation and Adenine Nucleotide Content in Lettré Ascites Cells

Summary

The relation between the phosphorylation of deoxyglucose (2-DG) and levels of adenine nucleotides was investigated in endogenously respiring Ehrlich Lettré ascites cells pretreated with various inhibitors. Pretreatment with the respiratory inhibitor, rotenone, caused a 70% decrease in 2-deoxyglucose-6-phosphate formation. The sources of energy for 2-DG phosphorylation in the presence of rotenone were found to be endogenous reserves of adenine nucleotides, as well as a limited residual respiration. Phosphorylation of 2-DG in the presence of 10^-4 m dinitrophenol was 70% of normal, and was abolished by addition of rotenone. Dinitrophenol was shown to induce a stoichiometric transamination of alanine to pyruvate, and cause a marked increase of ¹⁴CO₂ and pyruvate-¹⁴C from alanine-¹⁴C or glutamic acid-¹⁴C. The evidence suggests that substrate level phosphorylation from α-oxoglutarate and subsequent formation of adenosine triphosphate by a decarboxylation reaction is at least partially responsible for the phosphorylation of 2-DG in uncoupled cells.