Figure 1.

Intermediary metabolism in prostate epithelial cells. The major substrates and signaling pathways utilized in the truncated TCA cycle for citrate accumulation are depicted. The major substrates that are fed into the Krebs cycle are pyruvate via glucose, which may be converted to acetyl coA by pyruvate dehydrogenase and OAA by pyruvate decarboxylase. Glutamine is fed into the TCA cycle as α-ketoglutarate by the action of glutaminase and glutamate dehydrogenase. Aspartate is directly taken into the cell and transaminated by glutamate oxaloacetate transaminase into OAA. Purple represents enzymes, cofactors are presented in blue, glutaminolysis in green, nucleotides in red and substrates in black. OAA, oxaloacetate; TCA, tricarboxylic acid.