The standard free-energy change for the malate dehydrogenase reaction is a highly positive 29.7 kJ/mol. How does the reaction proceed in the forward direction in the cell?
Explanation
Reactions with a positive standard free-energy change can proceed in the forward direction if the products are maintained at a very low concentration, which makes the actual free-energy change (delta G) negative. This is the case for the malate dehydrogenase reaction, which is 'pulled' forward by the citrate synthase reaction.
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