Investigation of Magnesium Cation-proton Exchange with Transmembrane Electrostatically Localized Protons (TELP) at a Liquid-membrane Interface: Fundamental to Bioenergetics

The Lee transmembrane electrostatic proton localization (TELP) theory is a revolutionary scientific theory that has successfully explained decades long-standing quandary in the field of bioenergetics in regards to ATP synthesis in biological systems, specifically alkalophilic bacteria. This study provides experimental support for the TELP theory by further demonstrating evidence of a localized proton layer existing at the liquid-membrane interface in a simulated biological membrane apparatus. Whilst monovalent cations have been studied extensively, divalent cation exchange has not been studied experimentally. A previous study determined equilibrium constant for Na+ and K+ to exchange with localized H+ layer to be (5.07 ± 0.46) x 10-8 and (6.93 ± 0.91) x 10-8 respectively. We discovered that an equilibrium exchange occurs at 0.85 mM Mg2+ concentration. The findings here contributed to the successful determination of the equilibrium constant between Mg2+ and the localized H+ layer to be (1.56 ± 0.46) x 10-5. The equilibrium constant, much smaller than one, thus provides support for Lee’s TELP model since so many more Mg2+ in the bulk liquid phase that are required to even partially delocalize just a single H+ at the liquid-membrane interface. These results are relevant to further understand how water can act as a proton conductor for proton coupling energy transduction and the implications of different biological organisms’ salinity tolerance.https://digitalcommons.odu.edu/gradposters2022_sciences/1012/thumbnail.jp