The Entner-Doudoroff pathway, which is used by some microorganisms, including the talented Sinorhizobium meliloti:
1) Glucose + ATP ? Glucose-6-phosphate + ADP
2) Glucose-6-phospate + NADP+ ?6-Phosphogluconolactone + NADPH + H+
3) 6-Phosphogluconolactone + H2O ?6-Phosphogluconate
4) 6-Phosphogluconate ?2-Keto-3-deoxy-6-phosphogluconate
5) 2-Keto-3-deoxy-6-phosphogluconate ?Glyceraldehyde-3-phosphate + Pyruvate
6) Glyceraldehyde-3-phosphate + NAD+ + Pi ?1,3-Bisphosphateglycerate + NADH + H+
7) 1,3-Bisphosphateglycerate + ADP ?3-Phosphoglycerate + ATP
8) 3-Phosphoglycerate ?2-Phosphoglycerate
9) 2-Phosphoglycerate ?Phosphoenolpyruvate + H2O
10) Phosphoenolpyruvate + ADP ?Pyruvate + ATP
A. Which of the reactions above are also found in the glycolysis pathway we are studying in class?
B. How many (net) moles of ATP are produced per mole of glucose in the Entner-Doudoroff pathway? (Don't include any ATP made during the citric acid cycle or by oxidative phosphorylation.)
C. Assuming the organism uses pyruvate dehydrogenase and the citric acid cycle for aerobic growth, how many (net) moles of ATP (or ATP + GTP) would be produced per mole of glucose by substrate-level phosphorylation as a result of the action of the Entner-Doudoroff pathway and the citric acid cycle?
D. Identify the step(s) in the pathway above in which the metabolite is oxidized. Explain how you recognized that an oxidation-reduction reaction was taking place in this step (these steps).
E. Assuming the organism has pyruvate dehydrogenase, how many moles of acetyl-CoA would be produced per mole of glucose when it is growing aerobically using the Entner-Doudoroff pathway? Explain how you got your answer.
F. Again assuming the organism uses pyruvate dehydrogenase and the citric acid cycle for aerobic growth along with the Entner-Doudoroff pathway, how many moles of NADH plus NADPH would be produced per mole of glucose metabolized? Explain how you got your answer.