We investigated the proton conductance of the channel portion of chloroplast ATP synthase (CFa). Thylakoids were CFi-depleted by EDTA treatment. Proton pumps were stimulated by short flashes of light. Proton flux through CFo was measured spectrophotometrically in three different ways: as proton efflux from the lumen (via neutral red), charge flow across the membrane (via electrochromism) and pr...

Fuel cells hold great promise for wide applications in portable, residential, and large-scale power supplies. For low temperature fuel cells, such as the proton exchange membrane fuel cells (PEMFCs) and direct methanol fuel cells (DMFCs), proton-exchange membranes (PEMs) are a key component determining the fuel cells performance. PEMs with high proton conductivity under anhydrous conditions can...

Abstract Bioprotonic devices show promise for medicinal/therapeutic treatments because of their ability to deliver a controlled flow small molecules and ions living organisms. These rely on biocompatible, conductive polymer membranes facilitate molecular/ionic transport. Herein, ab initio molecular dynamics simulations are used probe the effects structure hydration level water diffusion in chit...

Channelrhodopsin (ChR)-1 and ChR2 were the first-identified members of ChRs which are a growing subfamily of microbial-type rhodopsins. Light absorption drives the generation of a photocurrent in cell membranes expressing ChR2. However, the photocurrent amplitude attenuates and becomes steady-state during prolonged irradiation. This process, called desensitization or inactivation, has been attr...

Cytochrome cbb(3) belongs to the superfamily of respiratory heme-copper oxidases that couple the reduction of molecular oxygen to proton translocation across the bacterial or mitochondrial membrane. The cbb(3)-type enzymes are found only in bacteria, and are both structurally and functionally the most distant from their mitochondrial counterparts. The mechanistic H(+)/e(-) stoichiometry of prot...

We present two models for electron-driven uphill proton transport across lipid membranes, with the electron energy converted to the proton gradient via the electrostatic interaction. In the first model, associated with the cytochrome c oxidase complex in the inner mitochondria membranes, the electrostatic coupling to the site occupied by an electron lowers the energy level of the proton-binding...

The development of novel membrane materials for hydrogen fuel cells, a promising environmentally friendly technology, represents relevant research task. In this work, we propose an approach to creating proton-conducting membranes from industrial polyethylene terephthalate (PET) dielectric track-etched film. An N, P-containing ionic liquid was used as modifying agent, whose polymerization carrie...