Download Cellular Respiration

Mitochondria
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 3.17a, b
Metabolism

Anabolism

Catabolism

Oxidative breakdown – nutrients are catabolized to
carbon dioxide, water, and ATP
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.3
Oxidation-Reduction (Redox) Reactions

Whenever one substance is oxidized, another
substance is reduced

Oxidized substances lose energy

Reduced substances gain energy

Coenzymes act as hydrogen (or electron) acceptors

Two important coenzymes are nicotinamide
adenine dinucleotide (NAD+) and flavin adenine
dinucleotide (FAD)
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Carbohydrate Metabolism
 Oxidation of glucose

C6H12O6 + 6O2  6H2O + 6CO2 + 36 ATP + heat

Glucose is catabolized in three pathways

Glycolysis

Krebs cycle

The electron transport chain and oxidative
phosphorylation
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Carbohydrate Catabolism
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.5
Glycolysis
Glycolysis
ATP
Krebs
cycle
ATP
Electron transport chain
and oxidative
phosphorylation
ATP
Glucose
Phase 1
Sugar
activation
Key:
= Carbon
atom
Pi = Inorganic
phosphate
2 ATP
2 ADP
Fructose-1,6bisphosphate
P
P
Phase 2
Sugar
Dihydroxyacetone
cleavage
phosphate
P
Pi
Glyceraldehyde
phosphate
P
2 NAD+
4 ADP
2 NADH+H+
Phase 3
Sugar
oxidation
and formation
of ATP
4 ATP
2 Pyruvic acid
2 NADH+H+
O2
To Krebs
cycle
(aerobic
pathway)
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
O2
2 NAD+
2 Lactic acid
Figure 24.6
Glycolysis
Glycolysis
ATP
Krebs
cycle
ATP
Electron transport chain
and oxidative
phosphorylation
ATP
Glucose
Phase 1
Sugar
activation
2 ATP
2 ADP
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Key:
= Carbon
atom
Pi = Inorganic
phosphate
Figure 24.6
Glycolysis
Glycolysis
ATP
Krebs
cycle
ATP
Electron transport chain
and oxidative
phosphorylation
ATP
Glucose
Phase 1
Sugar
activation
2 ATP
2 ADP
Fructose-1,6bisphosphate
P
P
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Key:
= Carbon
atom
Pi = Inorganic
phosphate
Figure 24.6
Glycolysis
Glycolysis
ATP
Krebs
cycle
ATP
Electron transport chain
and oxidative
phosphorylation
ATP
Glucose
Phase 1
Sugar
activation
2 ATP
2 ADP
Fructose-1,6bisphosphate
P
P
Phase 2
Sugar
Dihydroxyacetone
cleavage
phosphate
P
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Key:
= Carbon
atom
Pi = Inorganic
phosphate
Glyceraldehyde
phosphate
P
Figure 24.6
Glycolysis
Glycolysis
ATP
Krebs
cycle
ATP
Electron transport chain
and oxidative
phosphorylation
ATP
Glucose
Phase 1
Sugar
activation
2 ATP
2 ADP
Fructose-1,6bisphosphate
P
P
Phase 2
Sugar
Dihydroxyacetone
cleavage
phosphate
P
Pi
Key:
= Carbon
atom
Pi = Inorganic
phosphate
Glyceraldehyde
phosphate
P
2 NAD+
2 NADH+H+
Phase 3
Sugar
oxidation
and formation
of ATP
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.6
Glycolysis
Glycolysis
ATP
Krebs
cycle
ATP
Electron transport chain
and oxidative
phosphorylation
ATP
Glucose
Phase 1
Sugar
activation
2 ATP
2 ADP
Fructose-1,6bisphosphate
P
P
Phase 2
Sugar
Dihydroxyacetone
cleavage
phosphate
P
Pi
Key:
= Carbon
atom
Pi = Inorganic
phosphate
Glyceraldehyde
phosphate
P
2 NAD+
4 ADP
2 NADH+H+
Phase 3
Sugar
oxidation
and formation
of ATP
4 ATP
2 Pyruvic acid
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.6
Glycolysis
Glycolysis
ATP
Krebs
cycle
ATP
Electron transport chain
and oxidative
phosphorylation
ATP
Glucose
Phase 1
Sugar
activation
2 ATP
2 ADP
Fructose-1,6bisphosphate
P
P
Phase 2
Sugar
Dihydroxyacetone
cleavage
phosphate
P
Pi
Key:
= Carbon
atom
Pi = Inorganic
phosphate
Glyceraldehyde
phosphate
P
2 NAD+
4 ADP
2 NADH+H+
Phase 3
Sugar
oxidation
and formation
of ATP
4 ATP
2 Pyruvic acid
O2
To Krebs
cycle
(aerobic
pathway)
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.6
Glycolysis
Glycolysis
ATP
Krebs
cycle
ATP
Electron transport chain
and oxidative
phosphorylation
ATP
Glucose
Phase 1
Sugar
activation
Key:
= Carbon
atom
Pi = Inorganic
phosphate
2 ATP
2 ADP
Fructose-1,6bisphosphate
P
P
Phase 2
Sugar
Dihydroxyacetone
cleavage
phosphate
P
Pi
Glyceraldehyde
phosphate
P
2 NAD+
4 ADP
2 NADH+H+
Phase 3
Sugar
oxidation
and formation
of ATP
4 ATP
2 Pyruvic acid
2 NADH+H+
O2
To Krebs
cycle
(aerobic
pathway)
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
O2
2 NAD+
2 Lactic acid
Figure 24.6
Glycolysis:

The final products are:

Two pyruvic acid molecules

Two NADH + H+ molecules (reduced NAD+)

A net gain of two ATP molecules
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Cytosol
Pyruvic acid from glycolysis
Glycolysis
ATP
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
NAD+
CO2
CoA
Acetyl CoA
ATP
Mitochondrion
(fluid matrix)
NADH+H+
ATP
Oxaloacetic acid
(pickup molecule)
NADH+H+
Citric acid
CoA (initial reactant)
NAD+
Isocitric acid
Malic acid
NAD+
Krebs cycle
CO2
NADH+H+
a-Ketoglutaric acid
Fumaric acid
CO2
FADH2
FAD
Key:
Succinic acid
Succinyl-CoA
CoA
NAD+
NADH+H+
CoA
= Carbon atom
GTP
GDP + Pi
ADP
ATP
Pi = Inorganic phosphate
CoA = Coenzyme A
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.7
Krebs Cycle


An eight-step cycle in which
each acetic acid is
decarboxylated and oxidized,
generating:

Three molecules of NADH +
H+

One molecule of FADH2

Two molecules of CO2

One molecule of ATP
For each molecule of glucose
entering glycolysis, two
molecules of acetyl CoA enter
the Krebs cycle
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Pyruvic acid from glycolysis
Glycolysis
ATP
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
ATP
CO2
CoA
Acetyl CoA
Cytosol
NAD+
NADH+H+
Mitochondrion
(fluid matrix)
ATP
Key:
= Carbon atom
Pi = Inorganic phosphate
CoA = Coenzyme A
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.7
Pyruvic acid from glycolysis
Glycolysis
ATP
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
ATP
Cytosol
NAD+
CO2
CoA
Acetyl CoA
NADH+H+
Mitochondrion
(fluid matrix)
ATP
Oxaloacetic acid
(pickup molecule)
Citric acid
CoA (initial reactant)
Krebs cycle
Key:
= Carbon atom
Pi = Inorganic phosphate
CoA = Coenzyme A
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.7
Cytosol
Pyruvic acid from glycolysis
Glycolysis
ATP
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
ATP
NAD+
CO2
CoA
Acetyl CoA
NADH+H+
Mitochondrion
(fluid matrix)
ATP
Oxaloacetic acid
(pickup molecule)
Citric acid
CoA (initial reactant)
Isocitric acid
Krebs cycle
Key:
= Carbon atom
Pi = Inorganic phosphate
CoA = Coenzyme A
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.7
Cytosol
Pyruvic acid from glycolysis
Glycolysis
ATP
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
ATP
NAD+
CO2
CoA
Acetyl CoA
NADH+H+
Mitochondrion
(fluid matrix)
ATP
Oxaloacetic acid
(pickup molecule)
Citric acid
CoA (initial reactant)
Isocitric acid
NAD+
Krebs cycle
CO2
NADH+H+
a-Ketoglutaric acid
Key:
= Carbon atom
Pi = Inorganic phosphate
CoA = Coenzyme A
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.7
Cytosol
Pyruvic acid from glycolysis
Glycolysis
ATP
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
ATP
NAD+
CO2
CoA
Acetyl CoA
Mitochondrion
(fluid matrix)
NADH+H+
ATP
Oxaloacetic acid
(pickup molecule)
Citric acid
CoA (initial reactant)
Isocitric acid
NAD+
Krebs cycle
CO2
NADH+H+
a-Ketoglutaric acid
CO2
Succinyl-CoA
CoA
NAD+
NADH+H+
Key:
= Carbon atom
Pi = Inorganic phosphate
CoA = Coenzyme A
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.7
Cytosol
Pyruvic acid from glycolysis
Glycolysis
ATP
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
ATP
NAD+
CO2
CoA
Acetyl CoA
Mitochondrion
(fluid matrix)
NADH+H+
ATP
Oxaloacetic acid
(pickup molecule)
Citric acid
CoA (initial reactant)
Isocitric acid
NAD+
Krebs cycle
CO2
NADH+H+
a-Ketoglutaric acid
CO2
Succinic acid
Key:
Succinyl-CoA
CoA
NAD+
NADH+H+
CoA
= Carbon atom
GTP
GDP + Pi
ADP
ATP
Pi = Inorganic phosphate
CoA = Coenzyme A
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.7
Cytosol
Pyruvic acid from glycolysis
Glycolysis
ATP
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
NAD+
CO2
CoA
Acetyl CoA
ATP
Mitochondrion
(fluid matrix)
NADH+H+
ATP
Oxaloacetic acid
(pickup molecule)
Citric acid
CoA (initial reactant)
Isocitric acid
NAD+
Krebs cycle
CO2
NADH+H+
a-Ketoglutaric acid
Fumaric acid
CO2
FADH2
FAD
Key:
Succinic acid
Succinyl-CoA
CoA
NAD+
NADH+H+
CoA
= Carbon atom
GTP
GDP + Pi
ADP
ATP
Pi = Inorganic phosphate
CoA = Coenzyme A
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.7
Cytosol
Pyruvic acid from glycolysis
Glycolysis
ATP
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
NAD+
CO2
CoA
Acetyl CoA
ATP
Mitochondrion
(fluid matrix)
NADH+H+
ATP
Oxaloacetic acid
(pickup molecule)
Citric acid
CoA (initial reactant)
Isocitric acid
Malic acid
NAD+
Krebs cycle
CO2
NADH+H+
a-Ketoglutaric acid
Fumaric acid
CO2
FADH2
FAD
Key:
Succinic acid
Succinyl-CoA
CoA
NAD+
NADH+H+
CoA
= Carbon atom
GTP
GDP + Pi
ADP
ATP
Pi = Inorganic phosphate
CoA = Coenzyme A
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.7
Cytosol
Pyruvic acid from glycolysis
Glycolysis
ATP
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
NAD+
CO2
CoA
Acetyl CoA
ATP
Mitochondrion
(fluid matrix)
NADH+H+
ATP
Oxaloacetic acid
(pickup molecule)
NADH+H+
Citric acid
CoA (initial reactant)
NAD+
Isocitric acid
Malic acid
NAD+
Krebs cycle
CO2
NADH+H+
a-Ketoglutaric acid
Fumaric acid
CO2
FADH2
FAD
Key:
Succinic acid
Succinyl-CoA
CoA
NAD+
NADH+H+
CoA
= Carbon atom
GTP
GDP + Pi
ADP
ATP
Pi = Inorganic phosphate
CoA = Coenzyme A
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.7
Electron Transport Chain


Food (glucose) is oxidized and the released
hydrogens:

Are transported by coenzymes NADH and FADH2

Enter a chain of proteins bound to metal atoms
(cofactors)

Combine with molecular oxygen to form water

Release energy
The energy released is harnessed to attach
inorganic phosphate groups (Pi) to ADP, making
ATP by oxidative phosphorylation
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Glycolysis
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
ATP
ATP
ATP
H+
H+
H+
H+
Intermembrane
space
Core
Cyt c
e-
eQ
1
3
2
Inner
mitochondrial
membrane
2 H+ +
FADH2
NADH +
Mitochondrial
matrix
O2
H2O
FAD
ATP
ADP + Pi
H+
(carrying efrom food)
1
2
NAD +
H+
Electron Transport Chain
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
ATP Synthase
Figure 24.8
Glycolysis
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
ATP
ATP
ATP
H+
H+
H+
H+
Intermembrane
space
Core
Cyt c
e-
eQ
1
3
2
Inner
mitochondrial
membrane
2 H+ +
FADH2
NADH +
Mitochondrial
matrix
O2
H2O
FAD
ATP
ADP + Pi
H+
(carrying efrom food)
1
2
NAD +
H+
Electron Transport Chain
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
ATP Synthase
Figure 24.8
Glycolysis
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
ATP
ATP
ATP
H+
Core
Intermembrane
space
Cyt c
Q
1
3
2
Inner
mitochondrial
membrane
NADH + H+
(carrying efrom food)
Mitochondrial
matrix
NAD +
Electron Transport Chain
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.8
Glycolysis
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
ATP
ATP
ATP
H+
H+
Core
Intermembrane
space
Cyt c
eQ
1
3
2
Inner
mitochondrial
membrane
FADH2
NADH +
(carrying efrom food)
Mitochondrial
matrix
FAD
H+
NAD +
Electron Transport Chain
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.8
Glycolysis
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
ATP
ATP
ATP
H+
H+
H+
Core
Intermembrane
space
Cyt c
e-
eQ
1
3
2
Inner
mitochondrial
membrane
FADH2
NADH +
(carrying efrom food)
Mitochondrial
matrix
FAD
H+
NAD +
Electron Transport Chain
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.8
Glycolysis
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
ATP
ATP
ATP
H+
H+
H+
H+
Intermembrane
space
Core
Cyt c
e-
eQ
1
3
2
Inner
mitochondrial
membrane
FADH2
NADH +
(carrying efrom food)
Mitochondrial
matrix
FAD
H+
NAD +
Electron Transport Chain
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
ATP Synthase
Figure 24.8
Glycolysis
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
ATP
ATP
ATP
H+
H+
H+
H+
Intermembrane
space
Core
Cyt c
e-
eQ
1
3
2
Inner
mitochondrial
membrane
FADH2
NADH +
(carrying efrom food)
Mitochondrial
matrix
FAD
ATP
ADP + Pi
H+
NAD +
H+
Electron Transport Chain
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
ATP Synthase
Figure 24.8
Glycolysis
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
ATP
ATP
ATP
H+
H+
H+
H+
Intermembrane
space
Core
Cyt c
e-
eQ
1
3
2
Inner
mitochondrial
membrane
2 H+ +
FADH2
NADH +
Mitochondrial
matrix
O2
H2O
FAD
ATP
ADP + Pi
H+
(carrying efrom food)
1
2
NAD +
H+
Electron Transport Chain
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
ATP Synthase
Figure 24.8
Electronic Energy Gradient

The transfer of energy from NADH + H+ and
FADH2 to oxygen releases large amounts of energy

This energy is released in a stepwise manner
through the electron transport chain
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.9
Mechanism of Oxidative Phosphorylation

Electrons are delivered to oxygen, forming oxygen
ions

Oxygen ions attract H+ to form water

H+ pumped to the intermembrane space:

Diffuses back to the matrix via ATP synthase

Releases energy to make ATP
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Mechanisms of ATP Synthesis:
Oxidative Phosphorylation
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.4b
ATP Synthase

The enzyme consists of
three parts: a rotor, a knob,
and a rod

Current created by H+
causes the rotor and rod to
rotate

This rotation activates
catalytic sites in the knob
where ADP and Pi are
combined to make ATP
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Summary of ATP Production
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.11
Glycolysis
Krebs
cycle
Electron
transport chain
and oxidative
phosphorylation
ATP
ATP
ATP
H+
H+
H+
H+
Intermembrane
space
Core
Cyt c
e-
eQ
1
3
2
Inner
mitochondrial
membrane
2 H+ +
FADH2
NADH +
Mitochondrial
matrix
O2
H2O
FAD
ATP
ADP + Pi
H+
(carrying efrom food)
1
2
NAD +
H+
Electron Transport Chain
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
ATP Synthase
Figure 24.8
Fermentation
- Anaerobic
Glycolysis
ATP
Krebs
cycle
ATP
Electron transport chain
and oxidative
phosphorylation
ATP
Glucose
Phase 1
Sugar
activation
Key:
= Carbon
atom
Pi = Inorganic
phosphate
2 ATP
2 ADP
Fructose-1,6bisphosphate
P
P
Phase 2
Sugar
Dihydroxyacetone
cleavage
phosphate
P
Pi
Glyceraldehyde
phosphate
P
2 NAD+
4 ADP
2 NADH+H+
Phase 3
Sugar
oxidation
and formation
of ATP
4 ATP
2 Pyruvic acid
2 NADH+H+
O2
To Krebs
cycle
(aerobic
pathway)
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
O2
2 NAD+
2 Lactic acid
Figure 24.6