respiratory chain

4. Sources of high energy compound

5. Sources of high energy compound at substrate level

7. Oxidoreductases are classified into 4 groups:
oxidases, dehydrogenases,
hydroperoxidases and
oxygenases.

8. A- Oxidases :
These enzymes catalyze the removal of hydrogen
from a substrateusing oxygen as
a hydrogen acceptor. They form H2O
or H2O2 as follows:

9. B- Dehydrogenases:
These enzymes catalyze removal of hydrogen but cannot
use oxygen as a hydrogen acceptor. during the anaerobic
phase of glycolysis and respiratory chain.

10. C- Hydroperoxidases;
2- Catalase:
Any oxidoreductase that used to eliminate hydrogen peroxide include:
1- Peroxidase

11. Enzyme catalyzes the direct transfer and incorporation of O2 into a substrate
molecule include:
1- Dioxygenases = oxygen transferases= True
oxygenases
2-Monooxygenases= Mixed-function oxidases=
Hydroxylases
D- Oxygenases:

12. Oxidative phosphorylation (respiratory chain)
• The mitochondrial respiratory chain catalyzes the oxidation of fuel
molecules like NADH+H and FADH2 and transfers the electrons to
molecular oxygen with concomitant energy transduction into
adenosine triphosphate (oxidative phosphorylation)
• What are the components of respiratory chain?
• It is composed of four complexes (I, II, III and IV) plus carrier ,
(Coenzyme Q and cytochrome c).

13. Components of respiratory chain

21. Uncoupling protein
- Uncoupling protein (UCP): act as physiological uncoupler found
in inner mitochondrial membrane of mammals including humans.
- EXAMPLE:Thermogenin (UCP1) in the brown adipocytes of
mammals in newborn babies and hibernating animals is
responsible for the heat production due to uncoupling of
oxidation to phosphorylation.
- Synthetic uncouplers: 2,4-dinitrophenol