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Unformatted text preview: cle kJ reduce
FAD 400 -1000 -2000
But most of the energy
stored as electron energy
in reduced dinucleotides,
not as ATP -3000 MITOCHONDRION Where we’re going
1. Oxidative phosphorylation
a. Electron transport chain
3. Energy from fats matrix outer
membrane OXIDATIVE PHOSPHORYLATION
Electron Transport Chain H2 + 1/2 O2 200 Free energy (G) relati ve to O2 (kJ/mol e) Free energy, G Electron transport chain
is a series of proton pumps 160 120 80 40 series of downhill
redo x reactions G = - 241.6 kJ/mole H2O 0 Electron transport chain Still no ATP THE MYSTERY OF ATP
Efriam Racker (~1960): Substrate level phosphorylation
seemed to account for all of the ATP synthesis in the
cell. A Radical Solution: Chemiosmotic Hypothesis
A theory, proposed in 19611, that ATP synthesis in cells comes not from
substrate-level phosphorylation, but rather from the establishment of an
electro-chemical gradient across the inner membrane of the
mitochondrion using energy from NADH and FADH2 formed from the
breakdown of molecules such as glucose. Problems:
Where were the high-energy intermediate molecules?
Why were the enzymes always associated with the
Why was ATP synthesis so dependent upon maintaining
the mitochondrial structure? “Progress is made by young scientists who carry out
experiments that old scient...
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This note was uploaded on 12/21/2012 for the course BIOMG 1101 taught by Professor Colegilbert during the Fall '09 term at Cornell University (Engineering School).
- Fall '09