BB10a: Cells, Biomolecules

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BB10a Cells, Biomolecules Genetics, 2003
Semester 1.

• Thursday 16 Oct.
• Lecture
• Bioenergetics
• Andrew Pearson

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BB10A Bioenergetics
Bioenergetics is the study of energy
transformations in biological systems.
We have seen the E-M-P pathway, and noted that
glucose has a higher Gibbs Free energy content
than lactate. As the E-M-P proceeds, some of the
available ?G is used to phosphorylate ADP to make
ATP. The exergonic hydrolysis of ATP is used to
drive necessary endergonic biochemical reactions.
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BB10A Bioenergetics
From Brock
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BB10A Bioenergetics
From Brock
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Bioenergetics of Glycolysis
BB10A E-M-P pathway
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Energetics of glucose fermentation
From Brock
BB10A Bioenergetics
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BB10A Bioenergetics
The phosphorylation of ADP to make ATP during
fermentation is called substrate level
phosphorylation, because ADP is a simple enzymic
substrate in such reactions.
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Apart from the ?G available from the catabolism
of nutrient biomolecules, what else is available
to supply energy for biological systems?
BB10A Bioenergetics
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Apart from the ?G available from the catabolism
of nutrient biomolecules, what else is available
to supply energy for biological systems?
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BB10A Bioenergetics
The electron tower from Brock
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BB10A Bioenergetics
Let us calculate the amount of energy
theoretically available from the transfer of
electrons from NADH to oxygen
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BB10A Bioenergetics
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BB10A Bioenergetics
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BB10A Bioenergetics
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BB10A Bioenergetics
H
Inner membrane
H
Complex 1 Complex 2
There are many inner membrane oxidoreductases
that pass on electrons to Coenzyme Q (Ubiquinone)
From Lehninger
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BB10A Bioenergetics
Intermembrane space
Inner membrane
Only one inner membrane oxidoreductase can remove
electrons from Coenzyme Q
Matrix
Complex 3
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BB10A Bioenergetics
The inner membrane electron transport complex
that dumps electrons on to the terminal acceptor
oxygen.
Complex 4
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BB10A Bioenergetics
The only site of phosphorylation in the inner
membrane Complex 5
Protons pumped out by complexes 1, 3 4.
From Brock
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Apart from the ?G available from the catabolism
of nutrient biomolecules, what else is available
to supply energy for biological systems?
BB10A Bioenergetics
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Apart from the ?G available from the catabolism
of nutrient biomolecules, what else is available
to supply energy for biological systems?
BB10A Bioenergetics
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The energy in electromagnetic radiation can be
transferred to electrons, raising them to a high
energy state.
BB10A Bioenergetics
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BB10A Bioenergetics
Chlorophyll a
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BB10A Bioenergetics
Bacterial photochemical reaction centre
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BB10A Bioenergetics
Photosystem antenna reaction centre
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BB10A Bioenergetics
From Brock
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BB10A Bioenergetics
Anoxygenic photosystems
From Brock
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From Brock
Oxygenic photosystems
BB10A Bioenergetics
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BB10A Bioenergetics
From Brock
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BB10A Bioenergetics
Classification of organisms into bioenergetic
types
From Brock
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BB10A Bioenergetics
From Brock