Download Bacterial Reaction Centers overall reaction Interesting questions

Bacterial Reaction Centers
overall
reaction
2 Cytochrome c (red)
2 cytochrome c(red) + 2 protons + 2 photons--> 2 cyt c(ox) + QH2
Electron goes from P860 to HA to QA to QB.
UQ(ox) + 2e +H --> UQH2 (red) Em = 60 mV
-[cyt c(ox) + e = cyt c(red)]
Em= -(+250)
∆G° = -n∆E°= 60 + -2(250) = +440 meV
This is fueled by 2 photon of 860 nM (1246.4 eV/860=1.44 eV/photon)
efficiency = (440 meV out)/(2.88 meV in)=15%
You can also highlight the individual reactions along the pathway rather than
the first and last step.
You started this for the first talk but now think a bit more about the
energetics.
Interesting questions (one or 2)
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!"#$#%&#$#'#$#*+#()#!!+*#
Blue are protons binding
Red are electron transferring
Picture of protein core with reaction
(three that come to mind for me here; you should pick one for your system )
1) The cofactors are arranged so that there looks like there are two identical
pathways. Does the electron use one of them or both and why?
2) What is the energy of each step and are there any other competing
reaction pathways?
3) How does this compare to photosynthesis in green plants?
2 references
One that is your key review reference
One that has information about your interesting question