New Finding in Oxidative Phosphorylation: Isothermal Utilization of Latent Heat Energy by Electrostatically Localized Protons at Liquid‐Membrane Interface

Abstract

Upon application of a newly formulated equation for the proton motive force (pmf) across a biological membrane which takes electrostatically localized protons into account in elucidating the bioenergetics of oxidative phosphorylation in alkalophilic bacteria, it was shown that the localized protons at the liquid‐membrane interface dominate the total pmf. The decreasing trend of the pmf with higher pH values is due to the increasing exchange of cations with the localized protons and this trend matches excellently with the observed rapid increase in the bacteria population growth cell doubling times. It was revealed that the pmf from the isothermal latent heat utilization through the electrostatically localized protons is not constrained by the overall energetics of the redox‐driven proton pump system because (i) the localized protons are not free to move away from the membrane surface, (ii) the proton pumps embedded in the cell membrane extend beyond the localized proton layer, and (iii) the protonic inlet mouth of the ATP synthase that accepts protons is located within this layer. Remarkably, this new understanding agrees excellently with the true structures of mitochondrial respiratory protein complexes. It therefore appears that the oxidative phosphorylation system is able to isothermally utilize the latent heat energy effectively through electrostatically localized protons to help driving the synthesis of ATP.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.