ch22: carbohydrate metabolism - laney college · 2016-08-16 · [handout] catabolism flow chart...
TRANSCRIPT
Ch22:CarbohydrateMetabolism
Chem30B
CatabolismOverview
Diges;onofCarbohydrates
VilliofSmallIntes;ne
[Handout]CatabolismFlowChart
CARBOHYDRATES
Glucose 6-phosphate
LIPIDS
5-C sugars + NAPDH
Pentose PhosphatePathway Glycogenesis
Glycogen
Glucose +Other Sugars
H3C C
O
C
O
O-
Pyruvate
Acetyl-CoAH3C C
O
SCoA
3 NADH, 1 FADH2
Electron TransportChain & Oxidative
Phosphorylation
11 ATP(3 ATP/NADH + 2 ATP/FADH2)
Citric AcidCycle
2 NADH + 2 ATP
NADH
1 ATP 2 CO2
*Glycolysis yields 2 pyruvates, so multiply everything below by 2x!
O2
H2O
Fatty Acids + Glycerols
Fatty Acids
β-oxidation
n NADH+ n FADH2
Steroids
Ketone bodies
PROTEINS
Amino Acids
Amino AcidCatabolism
Protein metabolism
CO2
FOOD
Glycolysis
LactateAnaerobic
Aerobic
(n depends on carbonlength of fatty acid)
[Handout]Glycolysis
H
OH
OHH OH
OH H
OHexokinase
Glucose Glucose 6-phosphate
Glucose 6-phosphateisomerase
CH2OH
OH
H
CH2
OH H
H OHO
2-O3PO ADPATP
Fructose 6-phosphate kinaseCH2HO
H
OH
OHH OH
OH H
OCH22-O3PO
Fructose 6-phophate
CH2OPO32-
OH
H
CH2
OH H
H OHO
2-O3PO
Fructose 1,6-bisphosphate
Aldolase
H2C C
OCH2OH2-O3PO
CH
CHOH2
COH
Dihydroxyacetone phosphate
D-Glyceraldehyde3-phosphate
Triose phosphateisomerase
Glyceraldehyde 3-phosphate dehydrogenase
NADH/H+
1,3-Bisphosphoglycerate
ADP ATPPhosphoglycerate kinase
3-Phosphoglycerate
Phosphoglycerate mutase
2-Phosphoglycerate
Enolase H2O
2-O3PO CH
CO
OPO32-H2C
OH2-O3PO
CH
CO
O–H2C
OH2-O3PO C
HCO
O–H2C
OPO32–
HO C CO
O–H2C
OPO32–
Phosphoenolpyruvate
C CO
O–H3C
Pyruvate kinaseO
Pyruvate
ADP ATP
ADPATP
1 2 3
45
6
7 8 9
10
NAD+ HOPO32-
GlucosetoAcetyl-CoA
[Handout]ATPAccoun;ngforGlucoseCatabolism
H.KimforChem30B
3
GlucoseandFattyAcidCatabolism
I.GlucoseCatabolism A.StepsofGlucoseCatabolism1.Glycolysis:glucose+2NAD++2HOPO32-+2ADPà2pyruvate+2NADH+2ATP+2H2O+2H+
2.PyruvateOxidation:2pyruvate+2NAD++2HSCoAà2Acetyl-CoA+2CO2+2NADH+2H+3.CitricAcidCycle:2Acetyl-CoA+6NAD++2FAD+2ADP+2HOPO32-+4H2Oà2HSCoA+6NADH+6H++2FADH2+ 2ATP+4CO2 4.ElectronTransport/OxidativePhosphorylation:ElectronsfromalltheNADHandFADH2madeinthepreviousstepsareusedtoreduceO2towater: O2+4e-+4H+à2H2OThereleasedenergyisusedtomakeATP: 3ATPmade/1NADH 2ATPmade/1FADH2
(Moreaccurate:2.5ATP/NADH,1.5ATP/FADH2)
B.TotalATPCountforCatabolismofaGlucoseMolecule
• Glycolysis:2ATP+6ATP(from2NADH)=8ATP• Pyruvateoxidation:6ATP(from2NADH)=6ATP• CitricAcidCycle:2ATP+18ATP(from6NADH)+4ATP(from2FADH2)=24ATP
_________________________________________________________________________________________________________ TOTAL:38ATP