Lesson 6 Carbohydrate digestion. Glucose phosphorylation and metabolic
fates. Anaerobic and aerobic glycolysis and their control.
Concepts and terms
a.Explain glucose phosphorylation, its importance in metabolism, and its medical
application in PET
b.Glycolytic pathway, the relevance of oxidation steps and
substrate-level phosphorylation
c. Regulation of key glycolytic enzymes by local and hormonal control
d.Energy production from anaerobic and aerobic glycolysis, and Pasteur effect
e. How pyruvate produced by glycolysis can be converted to lactate, acetyl-CoA
and oxalacetate, and the control of these reactions
Reading assignment
Garrett 535-559, Campbell 481-503.
Animation viewing:
http://highered.mheducation.com/sites/0072507470/student_view0/chapter25/animati
on__how_glycolysis_works.html
Homework exercises
Campbell ,p.505, №1-3, 5,7,12,23,26,27,31,32,37,41.
In-class exercises
Choose correct answer
1. During vigorous exercise, pyruvate produced by glycolysis is converted to
A.
B.
C.
D.
acetate
lactate
monosodium phosphate
pyruvic acid
2. The conversion of pyruvate to lactate is catalysed by
A.
B.
C.
D.
pyruvate carboxylase
lactate dehydrogenase
pyruvate dismutase
pyruvate decarboxylase
3.Under aerobic condition pyruvate is converted by pyruvate dehydrogenase to
A.
B.
C.
phosphoenol pyruvate
acetyl CoA
lactate
D.
glyceraldehyde 3 phosphate
4. Aldolases splits fructose 1,6 biphosphate into
A.
B.
C.
D.
glyceraldehyde 3- phosphate
glyceraldehyde 3- phosphate and dihydroxyacetone phosphate
dihydroxyacetone phosphate
none of the above
5. Glycolysis reactions take place in
A.
B.
C.
D.
cytoplasm
cell membrane
cell wall
plasmids
6. In the Glycolysis reaction, for each glucose conversion how many ATP's are
produced?
A.
C.
4
1
B.
D.
2
3
7. In glycolysis which of the following enzymes brake carbon-carbon bond?
A. Aldolase
B Pyruvate kinase
C. Phosphoglycerate kinase
D. Phosphofructokinase-1
8. Which of the following enzymes catalyze NOT irreverible reaction in
glycolysis?
A. Hexokinase
B. Glucokinase
C. 3-phosphoglycerate kinase
D. Pyruvate kinase
9. Which of the following enzymes located mostly NOT in liver?
A. Glucokinase
B Hexokinase.
C. Pyruvate kinase
D. Pyruvate dehydrogenase.
10. Phosphoglycerate kinase produce ATP by:
A. Oxidative phosphorylation
B. Oxidative decarboxylation
C. Substrate level phosphorylation
D. Oxidative deamination
11. Pasteur effect is due to inhibition of glycolysis by high concentration of
A. CO2
B. ATP
C. ADP.
D. AMP.
12. Pyruvate can be converted into oxaloacetate by enzyme:
A. Pyruvate kinase
B. Lactate dehydrogenase
C. Pyruvate carboxylase
D. Oxaloacetate kinase
Supplementary data
Glucose
Glucose-6-P
Fructose-1,6-diP
Fructose-6-P
O
O
-
O P O
HO
H
H
OH
OH
OH
ATP
PO3H2
O
8
H2PO4
ATP
2
7
CH3
O
O
Phosphoenol
pyruvate
O
10
Figure 1. Glycolysis.
H
PO3H2
HO
Pyruvate
O
H2PO4
HO
OH
ADP
OH
H
4
5
NAD+
NADH
PO3H2
6
1. Glucokinase
2. Phosphogluco
isomerase
3. Phosphofructo
kinase-1
4. Aldolase
5. Triosophosphate
isomerase
PO3H2
O
O
HO
ATP
H2PO4
HO
ADP
O
HO
H2O
ADP
CH
O
H
ATP
-
O
1,3-bisphospho
glycerate
O
HO
H
-
O P O
O
OH
OH
-
HO
H
HO
O
3
O
H
3-phospho
glycerate
HO
-
OH
OH
O
O P O
O
OH
H
ADP
2
H
HO
2-phospho
glycerate
9
O H
H
OH
HO
H
-
H
H
-
O P O
O
1
O H
O
-
O
HO
O
OH
6. Glyceraldehyde phosphate
isomerase
7. Phosphoglycerate kinase
8. Phosphoglycerate mutase
9. Enolase
10. Pyruvate kinase
Glucose
Glucose 6phosphatase
Hexokinase
Glucose-6-P
Fructose-6-P
Phosphofructo
kinase1 (PFK1)
Fructose-1,6bisphosphatase
AMP
AMP
ATP
Fructose-1,6-diP
Citrate
Acetyl-CoA
Pyruvate
carboxylase
Inhibition
Activation
Figure 2. Glycolysis regulation.
Phosphoenol
pyruvate
Pyruvate
Pyruvate
kinase
ATP
Acetyl-CoA