The final product of cellular respiration is the proton motive force, formed by protons pumped out of the membrane and by the voltage due to all charges. While Mitchell's original theory considered pumped protons released immediately to the bulk external medium, that has been criticized. Today there is a good amount of research showing that protons like to remain confined in 2D in proximity with the membrane (one review here). This would explain how certain extremophiles can survive in very basic places (not many protons around), where the proton motive force, defined from the bulk pH, cannot sustain ATP synthesis.

As far as I have been able to discover, the existence of such “surface protons” has only been shown in vitro (e.g. in a sustained lipid bilayer).

Is there any experimental evidence of such “surface protons” in intact cells, i.e. in vivo?

The final product of cellular respiration is the proton motive force, formed by protons pumped out of the membrane and by the voltage due to all charges. While Mitchell’s original theory considered pumped protons released immediately to the bulk external medium, that has been criticized. Today there is a good amount of research showing that protons tend to remain confined in 2D in proximity with the membrane (one review can be found here). This would explain how certain extremophiles can survive in very basic niches (poor in protons), where the proton motive force, defined from the bulk pH, cannot sustain ATP synthesis.

As far as I have been able to discover, the existence of such “surface protons” has only been shown in vitro (e.g. in a sustained lipid bilayer).

Is there any experimental evidence of such “surface protons” in intact cells, i.e. in vivo?

The final product of cellular respiration is the proton motive force, formed by protons pumped out of the membrane and by the voltage due to all charges. While Mitchell's original theory considered pumped protons released immediately to the bulk external medium, that has been criticized. Today there is a good amount of research showing that protons like to remain confined in 2D in proximity with the membrane (one review here). This would explain how certain extremophiles can survive in very basic places (not many protons around), where the proton motive force, defined from the bulk pH, cannot sustain ATP synthesis.

But for what I could find, the existence of such "surface protons" has been shown only in-vitro (eg sustained lipid bilayer), but never in living cells. I'd like to know

• is there an experimental evidence of "surface protons" in a living system? do you have references?
• is their existence nowadays accepted in the community?

The final product of cellular respiration is the proton motive force, formed by protons pumped out of the membrane and by the voltage due to all charges. While Mitchell's original theory considered pumped protons released immediately to the bulk external medium, that has been criticized. Today there is a good amount of research showing that protons like to remain confined in 2D in proximity with the membrane (one review here). This would explain how certain extremophiles can survive in very basic places (not many protons around), where the proton motive force, defined from the bulk pH, cannot sustain ATP synthesis.

As far as I have been able to discover, the existence of such “surface protons” has only been shown in vitro (e.g. in a sustained lipid bilayer).

Is there any experimental evidence of such “surface protons” in intact cells, i.e. in vivo?