2017 Biochemistry - Glycolysis Flashcards

1
Q

Reactants and Products of Hexokinase/Glucokinase - Step 1?

A

Glucose + ATP -> G6P

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Reactants and Products of Phosphofructokinase - Step 3?

A

Fructose-6-P + ATP -> Fructose-1,6-bisphosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Reactants and Products of Pyruvate Kinase - Step 9?

A

Phosphoenolpyruvate + ADP -> Pyruvate + ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Which steps of Glycolysis produce ATP?

A

Step 6 & 9

Phosphoglycerate kinase and Pyruvate Kinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which steps of Glycolysis use ATP?

A

Step 1 & 3

Hexokinase/Glucokinase and Phosphofructokinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the 3 enzymes responsible for the irreversible steps of Glycolysis?

A

Hexokinase/Glucokinase - step 1
Phosphofructokinase - step 3
Pyruvate kinase - step 9 & final step

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Differences/Similarities between Hexokinase and Glucokinase?

A

Glucokinase - present only in liver, kidney and B cells, low affinity = function is to remove glucose from blood following a meal, not inhibited by G6P.

Hexokinase - present in all tissues, very high affinity = saturated under normal condition and acts as a constant rate, Inhibited by G6P

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Aerobic Glycolysis; products, ATP produced, shuttle system

A
  • Pyruvate is converted to acetyl-CoA in mitocondria for TCA cycle
  • Oxidation of ACoA will lead to 36 ATP produced
  • Under aerobic conditions NADH which is produced may be re-oxidized by mitochondria through a shuttle system.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Primary purpose of Anaerobic Glycolysis?

A

To regenerate NAD+ using the G3P shuttle.
This allows NADH equivalents to get out of the mitochondria.
Pyruvate is reduced to Lactate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the inhibitors of Hexokinase?

A

Glu-6-P, ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the Activators/Inhibitors of PFK-1?

A

Activators: F-2,6-bP, AMP
Inhibitors: Citrate, ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the Activators/Inhibitors of Pyruvate Kinase?

A

Activators: F-2,6-bP, AMP
Inhibitors: Acetyl-CoA, ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What enzyme is used in Erythrocytes to bypass the “normal” route from Glyceraldehyde-3-p –> 3-Phosphoglycerate, which product is made in place of 1,3-bPG and what is it’s importance?

A

Biophosphglycerate mutase

2,3-bPG is made in RBCs which binds to Hb and decreases it’s affinity for O2, thus freeing O2 for use in tissue.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the 3 enzymes important to fructose metabolism?

A

Fructokinase: Fructose + ATP -> Fructose-1-p
Adolase B: Fructose-1-p Glyceraldehyde + Dihydroxyacetone phosphate
Triose Kinase: Glyceraldehyde + ATP -> Glyceraldehyde-3-phos.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Which enzyme of fructose metabolism is blocked in Essential Fructosuria?

A

Fructokinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Which enzyme of fructose metabolism is blocked in Hereditary Fructose Intolerance?

A

Aldolase B

17
Q

Galactose metabolism: important enzymes and resultant product

A
  1. Galactokinase
  2. UPD-Glc:Gal-1-P uridylyltransferase
  3. Phosphoglucomutase

Results in Glucose-6-P production

18
Q

Which enzyme is lacking/faulty in Galactosemia?

A

Galactose-1-phosphate uridyltransferase

19
Q

Mannose metabolism: important enzymes and resultant products

A
Mannose Kinase (liver) converts mannose to Mannose-6-P
Phosphomannose isomerase catalyzes Mannose-6-P to F-6-P
20
Q

One molecule of glucose converts to how many molecules of pyruvate through Glycolysis?

A

1 molecule glucose = 2 molecules of pyruvate