Generation of an electrochemical proton gradient is the first step of cell bioenergetics. In prokaryotes, the gradient is created by outward membrane protein proton pumps. Inward plasma membrane native proton pumps are yet unknown. We describe comprehensive functional studies of the representatives of the yet noncharacterized xenorhodopsins from Nanohaloarchaea family of microbial rhodopsins. They are inward proton pumps as we demonstrate in model membrane systems, Escherichia coli cells, human embryonic kidney cells, neuroblastoma cells, and rat hippocampal neuronal cells. We also solved the structure of a xenorhodopsin from the nanohalosarchaeon Nanosalina (NsXeR) and suggest a mechanism of inward proton pumping. We demonstrate that the NsXeR is a powerful pump, which is able to elicit action potentials in rat hippocampal neuronal cells up to their maximal intrinsic firing frequency. Hence, inwardly directed proton pumps are suitable for light-induced remote control of neurons, and they are an alternative to the well-known cation-selective channelrhodopsins.
- MeSH
- Archaea metabolismus MeSH
- buněčné linie MeSH
- Escherichia coli metabolismus MeSH
- koncentrace vodíkových iontů MeSH
- konformace proteinů MeSH
- lidé MeSH
- liposomy MeSH
- molekulární modely MeSH
- optogenetika * metody MeSH
- protonové pumpy metabolismus MeSH
- protony MeSH
- retina metabolismus MeSH
- rodopsin chemie metabolismus MeSH
- spektrální analýza MeSH
- světlo MeSH
- vazba proteinů MeSH
- vazebná místa MeSH
- vysokoúčinná kapalinová chromatografie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
