Share
Explore BrainMass

# Analysis of electron transport system

Analysis of an electron transport system in the cell membranes of a previously
unknown Kingdom of organisms revealed that it contained the following components
with the redox half-reactions and standard reduction potentials shown in the Table.

Half-Reaction E'o(V)

Cytochrome R+ + e &#8594; Cytochrome R +0.35
Cytochrome T+ + e &#8594; Cytochrome T +0.20
Fp 73+ + e &#8594; Fp 73 -0.22
NO3- + 2H+ + 2e &#8594; NO2 - + H2O +0.42

how to Calculate &#916;Go' for the transfer of a pair of electrons between each of the
carriers in the electron transport system. use the

Nernst equation from this data determine :

i)the steps at which sufficient energy is released to transfer protons across the membrane, assuming &#916;Go' for proton transfer against its concentration gradient is 23 kJ per mole of protons.

ii. for one electron pair, the amount of potential energy in the proton gradient which is theoretically available for ATP synthesis under standard conditions. (pls show how you decided on this)

iii. the number of ATP molecules which could theoretically be synthesised per electron pair. (please show how u decided on this)

#### Solution Preview

I will show you how to do this and then you can finish it on your own. Sound fair? But don't worry, I'll guide you through the steps carefully.

Half-Reaction E'o(V)

Cytochrome R+ + e &#8594; Cytochrome R +0.35
Cytochrome T+ + e &#8594; Cytochrome T +0.20
Fp 73+ + e &#8594; Fp 73 -0.22
NO3- + 2H+ + 2e &#8594; NO2 - + H2O +0.42

First, we have to put these half-reactions in order. So, let's put them in order.

NO3- + 2H+ + 2e &#8594; NO2 - + H2O +0.42
Cytochrome R+ + e &#8594; Cytochrome R +0.35
Cytochrome T+ + e &#8594; Cytochrome T +0.20
Fp 73+ + e &#8594; Fp 73 -0.22