In the reductive pentose phosphate cycle (Calvin cycle), which enzyme catalyzes the first irreversible, exergonic step that is not the fixation step?
Explanation
The Calvin cycle, while cyclical, is driven forward by three essentially irreversible, exergonic steps that ensure a net flow toward carbohydrate synthesis. These are the reactions catalyzed by fructose 1,6-bisphosphatase, sedoheptulose 1,7-bisphosphatase, and ribulose 5-phosphate kinase. The first of these after the initial fixation is the FBPase-1 step.
Other questions
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