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Considering the ATP synthase to be a rotating machine, does anybody know its power consumption and/or power production in Watts? At least roughly, e.g. based on the average chemical energy produced per time unit?

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    $\begingroup$ Watts? Science uses SI units. The joule is the unit of energy. Anyway, you are expected to demonstrate that you have done some of your own research before posting on this site. What have you done? What do you think the input is? What do you think the output is? We welcome you to SE Biology, but ask you please take the Tour read the Help before posting. $\endgroup$ – David Jan 28 '18 at 21:47
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    $\begingroup$ @David It's great that you want to help new posters write better questions, but in this case your comment is insulting for no reason. The Watt is the SI unit of power (1W=1J/s) and the question seems completely reasonable, just needing a pointer to the right literature. $\endgroup$ – Victor Chubukov Jan 29 '18 at 6:21
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    $\begingroup$ @David Science routinely uses non-SI units. $\endgroup$ – canadianer Jan 29 '18 at 8:08
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    $\begingroup$ @David I fully agree that SI-derived unit Joule [kg⋅m2⋅s−2] is the unit of energy, but I am interested in power and, therefore, used the SI-derived unit Watt [W] ([kg⋅m2⋅s−3]). $\endgroup$ – UweD Jan 29 '18 at 8:26
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    $\begingroup$ @VictorChubukov — You may not be aware that when you have achieved a certain SE Biology "reputation" you are expected to participate in the reviewing process, one aspect of which is reviewing posts by new users "This is the first question asked by a new user. Help them learn to use the site by reviewing their post." I indicated the particular parts of the Help that would allow him to see why his question — although interesting — did not conform to SE Biology guidelines, and gave concrete examples of points to research or mention in his question. I do not regard this as an insult. $\endgroup$ – David Jan 29 '18 at 11:00
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There are tons of mechanistic studies of ATP synthase so you may be able to get a better answer from finding one of those. But here's a rough estimate based on thermodynamics and enzyme kinetics.

The $\Delta G$ of ATP synthesis/hydrolysis is about -50 kJ/mol. The $V_{max}$ is in the low hundreds (here is an estimate of 350 $s^{-1}$ for E. coli ATP synthase), giving you something like 17 MW/mol or 30 aW (3e-17 W) /molecule.

I did look briefly at some mechanistic studies, and found this reference of 80 pN * nM for the torque generated. That translates to almost exactly the same 50 kJ/mol (ATP synthase is very efficient). But of course you still need the $V_{max}$ (number of rotations per second) to get the power.

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  • $\begingroup$ Thank you very much! This was exactly what I was looking for. $\endgroup$ – UweD Jan 29 '18 at 8:34

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