What are the Phases of the Pentose Phosphate Pathway?
The PPP is divided into two distinct phases: the oxidative phase and the non-oxidative phase.
Oxidative Phase This phase generates NADPH and involves the conversion of glucose-6-phosphate into ribulose-5-phosphate. The key enzyme in this phase is glucose-6-phosphate dehydrogenase (G6PD), which catalyzes the first step and is a regulatory point for the pathway.
Non-Oxidative Phase In this phase, ribulose-5-phosphate is converted into ribose-5-phosphate and other sugars that can enter glycolysis. Key enzymes include transketolase and transaldolase, which facilitate the rearrangement of carbon skeletons.
