Download 2 H +

Light
energy
ECOSYSTEM
Photosynthesis
in chloroplasts
CO2 + H2O
Organic
+ O molecules
2
Cellular respiration
in mitochondria
ATP
ATP powers most cellular work
Heat
energy
1
becomes oxidized
(loses electron)
becomes reduced
(gains electron)
2
becomes oxidized
becomes reduced
3
Reactants
Products
becomes oxidized
becomes reduced
Methane
(reducing
agent)
Oxygen
(oxidizing
agent)
Carbon dioxide
Water
4
becomes oxidized
becomes reduced
5
Dehydrogenase
6
2 e– + 2 H+
2 e– + H+
NADH
H+
Dehydrogenase
NAD+
+
2[H]
Reduction of NAD+
+
H+
Oxidation of NADH
Nicotinamide
(reduced form)
Nicotinamide
(oxidized form)
7
Free energy, G
r
nspo
Explosive
release of
heat and light
energy
+
2 H
(from food via NADH)
Controlled
release of
+
–
2 H + 2 e energy for
synthesis of
ATP
ATP
tra
tron
Elec n
chai
Free energy, G
H2 + 1/2 O2 ATP
ATP
t
2 e–
2
1/ O 2 2
H+
H2O
(a) Uncontrolled reaction
1/ O 2 2
H2O
(b) Cellular respiration
8
Electrons carried
via NADH and
FADH2
Electrons
carried
via NADH
Glycolysis
Pyruvate
Glucose
Citric
acid
cycle
Oxidative
phosphorylation:
electron transport
and
chemiosmosis
Mitochondrion
Cytosol
ATP
ATP
ATP
Substrate-level
phosphorylation
Substrate-level
phosphorylation
Oxidative
phosphorylation
9
Enzyme
Enzyme
ADP
P
Substrate
+
ATP
Product
10
Energy investment phase
Glucose
2 ADP + 2
P
2 ATP
used
4 ATP
formed
Energy payoff phase
4 ADP + 4
P
2 NAD+ + 4 e– + 4 H+
2 NADH
+ 2 H+
2 Pyruvate + 2 H2O
Net
Glucose
4 ATP formed – 2 ATP used
2 NAD+ + 4 e– + 4 H+
2 Pyruvate + 2 H2O
2 ATP
2 NADH + 2 H+
11
Glucose
ATP
1
Hexokinase
ADP
Glucose-6-phosphate
2
Phosphoglucoisomerase
Fructose1, 6-bisphosphate
4
Fructose-6-phosphate
ATP
Aldolase
3
Phosphofructokinase
ADP
5
Isomerase
Fructose1, 6-bisphosphate
4
Aldolase
5
Isomerase
Dihydroxyacetone
phosphate
Dihydroxyacetone
phosphate
Glyceraldehyde3-phosphate
Glyceraldehyde3-phosphate
12
2 NAD+
6
Triose phosphate
dehydrogenase
2
P
i
2
NADH
+ 2 H+
2
1, 3-Bisphosphoglycerate
2 ADP
7
Phosphoglycerokinase
2 ATP
2
Phosphoenolpyruvate
2 ADP
2
3-Phosphoglycerate
8
10
Pyruvate kinase
Phosphoglyceromutase
2 ATP
2
2-Phosphoglycerate
9
2 H2O
Enolase
2
Phosphoenolpyruvate
2 ADP
10
Pyruvate kinase
2 ATP
2
2
Pyruvate
Pyruvate
13
CYTOSOL
MITOCHONDRION
NAD+
NADH
+ H+
2
1
Pyruvate
3
CO2
Coenzyme A
Acetyl CoA
Transport protein
14
Pyruvate
CO2
NAD+
CoA
NADH
+ H+
Acetyl CoA
CoA
CoA
Citric
acid
cycle
FADH2
2
CO2
3 NAD+
3
NADH
FAD
+ 3 H+
ADP +
P
i
ATP
15
Acetyl CoA
CoA—SH
NADH
+H+
H2O
1
NAD+
8
Oxaloacetate
2
Malate
Citrate
Isocitrate
NAD+
H2O
Citric
acid
cycle
7
Fumarate
6
CO2
CoA—SH
4
CoA—SH
5
FADH2
NADH
+ H+
3
NAD+
FAD
Succinate
GTP
GDP
P
i
Succinyl
CoA
α-Ketoglutarate
CO2
NADH
+ H+
ADP
ATP
16
NADH
50
2
e–
NAD+
FADH2
2
e–
Free energy (G) relative to O2 (kcal/mol)
40
FMN
Ι
FAD
Multiprotein
complexes
FAD
Fe•S
ΙΙ
Fe•S
Q
ΙΙΙ
Cyt b
30
Fe•S
Cyt c1
IV
Cyt c
Cyt a
20
10
0
Cyt a3
2
e–
(from NADH
or FADH2)
2 H+ + 1/2
O2
H2O
17
INTERMEMBRANE SPACE
H+
Stator
Rotor
Internal
rod
Catalytic
knob
ADP
+
P
i
ATP
MITOCHONDRIAL MATRIX
18
H+
H+
H+
Protein complex
of electron
carriers
H+
Cyt c
ΙV
Q
ΙΙΙ
Ι
ΙΙ
FADH2
NADH
FAD
ATP
synthase
2 H+ + 1/2O2
NAD+
H2O
ADP +
P
i
(carrying electrons
from food)
ATP
H+
1
Electron transport chain
2
Chemiosmosis
Oxidative phosphorylation
19
CYTOSOL
Electron shuttles
span membrane
2 NADH
Glycolysis
2
Glucose
Pyruvate
MITOCHONDRION
2 NADH
or
2 FADH2
6 NADH
2 NADH
2
Acetyl
CoA
+ 2 ATP
Citric
acid
cycle
+ 2 ATP
Maximum per glucose:
2 FADH2
Oxidative
phosphorylation:
electron transport
and
chemiosmosis
+ about 32 or 34 ATP
About
36 or 38 ATP
20
2 ADP + 2
Pi
Glucose
2 ATP
Glycolysis
2 Pyruvate
2 NAD+
2 NADH
+ 2 H+
2
CO2
2 Acetaldehyde
2 Ethanol
(a) Alcohol fermentation
2 ADP + 2
Pi
Glucose
2 ATP
Glycolysis
2 NAD+
2 NADH
+ 2 H+
2 Pyruvate
2 Lactate
(b) Lactic acid fermentation
21
Glucose
CYTOSOL
Glycolysis
Pyruvate
No O2 present:
Fermentation
O2 present:
Aerobic cellular
respiration
MITOCHONDRION
Ethanol
or
lactate
Acetyl CoA
Citric
acid
cycle
22
Proteins
Carbohydrates
Amino
acids
Sugars
Fats
Glycerol
Fatty
acids
Glycolysis
Glucose
Glyceraldehyde-3-
P
NH3
Pyruvate
Acetyl CoA
Citric
acid
cycle
Oxidative
phosphorylation
23
Glucose
Glycolysis
Fructose-6-phosphate
–
AMP
Stimulates
+
Phosphofructokinase
–
Fructose-1,6-bisphosphate
Inhibits
Inhibits
Pyruvate
ATP
Citrate
Acetyl CoA
Citric
acid
cycle
Oxidative
phosphorylation
24