Lee's transient protonic capacitor cannot explain the surface proton current observed in bacteriorhodopsin purple membranes

Biophys Chem. 2023 Aug 15;301:107096. doi: 10.1016/j.bpc.2023.107096. Online ahead of print.ABSTRACTRecently in this Journal, James Lee employed his transmembrane electrostatically localized proton (TELP) hypothesis and the notion of a transient protonic capacitor to explain the force holding protons at the surface of bacteriorhodopsin purple membrane fragments. Here we show that purple membrane fragments cannot maintain the requisite transient non-zero transmembrane potential, and even if they could, it would not support the surface proton current moving from the P side to the N side that was reported by Heberle et al. (Nature, 1994). Currently accepted models explain the force keeping protons at the membrane surface by invoking the unusual structure of water at the interface which serves to stabilize the proton (energy well) and/or raise the activation ∆G‡ (energy barrier) for release to the bulk phase. Any future invocations of TELP should be required to include experimental measurements carried out at the surfaces of lipid bilayer membranes and/or biological membranes.PMID:37604049 | DOI:10.1016/j.bpc.2023.107096

Source: Biophysical Chemistry - August 21, 2023 Category: Chemistry Authors: Todd P Silverstein Source Type: research