Electron Transport Chain

Complexes associated with the electron transport chain, ATP synthesis.

1. Electron Transport Chain

Intermembrane space

Mitochondrial matrix Inner mitochondrial membrane

2. FADH, FAD

U

Complex II
NADH $0,42H"
à » Ha Cyt c Gis
H’+NAD"-
Complex I Complex III Complex IV

Figure 2,9: Overview oflelectron flow through the respiratory chain (Q, co-enzyme Q; Cyt, cytochrome).

3. Intermembrane
space

RAARARAR | Inner mitochondrial
VV) | membrane
¡600000
Mitochondrial
matrix
an“ 2H
Intermembrane
space

2e JE
© sam >

Inner mitochondrial

membrane
Complex III

Mitochondrial

2 matrix

1 +
FADH, FAD 30,+2H HO

Figure 2.13 Flow of electrons through the respiratory chain complexes, showing the entry points for reducing equiv-
alents, Q and cyt care mobile components of the system.

4. The Electron Transport Chain
w ur ut
Intermembrane Space

ut

Wout He

BEN ne
Matrix Electron Transport Chain =
Chemiosmasis

‘The Electron Transport Chain is a series of electron camiers in the Inner membrane of the mitochondria. Electrons are passed from NADH to oxygen, moving photons (H*)
rom the matrix to the intermembrane space, FADH2 also donates electrons to tha chain, relaasing hydrogen ions into the intermembrane space, Eventually, the high He
coneentation inthe intermembrane spac use some ol he ons Lo ow down the raten gd and back it he mat trough ATP synthe, ring ATP |

Whitney, E., & Rolfes, S. (2002). Energy Metabolism. In Understanding Nutrition (th ed.). Belmont, California: Wadsworth.

5. Summary of ATP synthesis from the oxidation of one molecule of glucose
NADH FADH,

Glycolysis (cytoplasm)
Glucose —> Glucose-6-phosphate
6-phosphate —; Fructose-1,6-bisphosphate

+2

Fructose-
-phosphate —> 2 Glycerate-1,3-bisphosphate

2 Glyceraldehyde-3
2 Glycerate-1,3-bisphosphate — 2 Glycerate-3-phosphate

2 Phosphoenolpyruvate — ; 2 Pyruvate

Mitochondrial reactions
2 Pyruvate — 2 Acetyl-CoA +2
Citric acid cycle
2 Isocitrate —> 2 a-ketoglutarate +2
2 a-ketoglutarate —> 2 Succinyl-CoA +2
2 Succinyl-CoA —> 2 Succinate
+2
+2

2 Succinate — 2 Fumarate

2 Malate —> 2 Oxaloacetate
10 NADH 2 FADH,

+2
+2

+2

4ATP