Ch. 9 Flashcards
What are the steps of glycolysis (substrates, products and enzymes)?
- Hexokinase or glucokinase
- Phosphoglucoisomerase
- Phosphofructokinase-1
- Aldolase
- Triose phosphate isomerase
- Glyceraldehyde-3-phosphate dehydrogenase (GAPDH)
- Phosphoglycerate kinase
- Phosphoglyceromutase
- Enolase
- Pyruvate kinase
What is reaction 1 of glycolysis?
Hexokinase or glucokinase
- Works via induced-fit mechanism
- Phosphorylation reaction
- ATP hydrolysis
- Mg2+ required
What is reaction 2 of glycolysis?
Phosphoclucoisomerase
- Isomerization
What is reaction 3 of glycolysis?
Phosphofructokinase-1
- Phosphorylation
- ATP hydrolysis
- Rate-limiting step of entire pathway
What is reaction 4 of glycolysis?
Aldolase
- Cleavage
- Uses Schiff base as intermediate
What is reaction 5 of glycolysis?
Triose phosphate isomerase
- Isomerization
- 2 G-3-P are used in the subsequent steps of glycolysis
- End of ATP investment stage
What is reaction 6 of glycolysis?
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH)
- Phosphoryl group transfer
- Produces 2 NADH (1 per G-3-P)
What is reaction 7 of glycolysis?
Phosphoglycerate kinase
- Substrate-level phosphorylation
- Produces 2 ATP - first time ATP made in glycolysis; substrate level phosphorylation
What is reaction 8 of glycolysis?
Phosphoglyceromutase
- Phosphoryl shift
What is reaction 9 of glycolysis?
Enolase
- Dehydration
What is reaction 10 of glycolysis?
Pyruvate kinase
- Substrate-level phosphorylation
- Produces 2 ATP
Which stage of glycolysis is ATP investment?
Stage 1 (reactions 1-5)
Which stage of glycolysis is ATP production?
Stage 2 (reactions 6-10)
What are the differences between stage 1 and 2 of glycolysis?
Stage 1 is ATP investment while Stage 2 is ATP production
What are high energy intermediates and why are they important?
- 1,3 bisphosphoglycerate
- phosphoenolpyruvate
- transfer phosphate groups or hydride ions
Where does oxidation-reduction take place (step, enzyme, substrates and products)?
- Glyceraldehyde-3-phosphate
- 1st high energy intermediate: 1st high energy intermediate: 1,3 biphosphoglycerate (2 per glucose)
- Generates NADH (2 NADH/glucose)
- Phosphoryl group transfer
Where does NADH go after glycolysis with and without oxygen? Why is this important to have NAD+ again?
How does regulation work?
How do substrates or molecules before a reaction effect that reaction or subsequent reactions?
How do products of immediate reactions or distant reactions change those reactions?
How do stage 2 products affect stage 1 of glycolysis for example?
What does an allosteric graph look like? What do the 3 curves represent?
How is glycolysis regulated?
review briefly sugars as shown in the ppt.
How do you link to reactions together to obtain a favorable delta G (free energy) and calculate the values?