Allosteric Effects of the Proton Donor on the Microbial Proton Pump Proteorhodopsin.

ABSTRACT: Proteorhodopsin (PR) is a microbial proton pump that is ubiquitous in marine environments and may play an important role in the oceanic carbon cycle. Photoisomerization of the retinal chromophore in PR leads to a series of proton transfers between specific acidic amino acid residues and the Schiff base of retinal, culminating in a proton motive force to facilitate ATP synthesis. The proton donor in a similar retinal protein, bacteriorhodopsin, acts as a latch to allow the influx of bulk water. However, it is unclear if the proton donor in PR, E108, utilizes the same latch mechanism to become internally hydrated. Here, we used molecular dynamics simulations to model the changes in internal hydration of the blue variant of PR during photoactivation with the proton donor in protonated and dep

SUBMITTER: Faramarzi S 

PROVIDER: S-EPMC6170653 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature