Pentose Phosphate Pathway Flashcards
Which other metabolic process does the PPP mirror?
The Calvin Cycle
What are the two key Phases of the PPP?
Phase 1 = oxidative generation of NADPH
Phase 2 = non-oxidative (reversible)
Which organisms does the PPP take place?
ALL!
Where does the PPP take place?
Cytoplasm
What is the starting molecule in the PPP?
Glucose-6-Phosphate G6P
(Simply) Why are there different fates of G6P?
Dependent on cell’s requirements
What are the 2 main products of the first phase of the PPP?
Ribose 5-phosphate and Xylulose-5-phosphate
What are the intermediates between the oxidative decarboxylation of glucose 6-phosphate to ribulose 5-phosphate (6C to 5C)? PPP?
6-phsphoglucono-delta-lactone
then phosphogluconate
What carriers and small molecules are produced in the 1st, 2nd and 3rd step of converting G6P to ribulose 5-phosphate? PPP
1st = NADPH
2nd = H2O used to produce H+
3rd = NADPH and CO2
What enzyme is used in the first step of the conversion of G6P to ribulose 5-phosphate?
glucose 6-phosphate dehydrogenase
What enzyme is involved in the 2nd step in the oxidative decarboxylation of G6P to ribulose 5-phosphate?
lactonase
What enzyme is involved in the 3rd step in the oxidative decarboxylation of G6P to ribulose 5-phosphate?
6-phosphogluconate dehydrogenase
Which product of the first phase of the PPP can be diverted to other pathways?
Ribose -5- phosphate
Which enzyme is used in the reversible reaction producing ribose 5-phosphate in the first stage of the PPP?
phosphopentose isomerase
Which reaction does the enzyme phosphopentose epimerase catalyse in the PPP?
ribulose 5-phosphate to xylulose 5-phosphate