Mutational analysis of the conserved carboxylates of anion channelrhodopsin-2 (ACR2) expressed in Escherichia coli and their roles in anion transport.

ABSTRACT: Anion channelrhodopsin-2 (ACR2), a light-gated channel recently identified from the cryptophyte alga Guillardia theta, exhibits anion channel activity with exclusive selectivity. In addition to its novel function, ACR2 has become a focus of interest as a powerful tool for optogenetics. Here we combined experimental and computational approaches to investigate the roles of conserved carboxylates on the anion transport activity of ACR2 in Escherichia coli membrane. First, we replaced six conserved carboxylates with a neutral residue (i.e. E9Q, E56Q, E64Q, E159Q, E219Q and D230N), and measured anion transport activity using E. coli expression system. E159Q and D230N exhibited significantly lower anion transport activity compared with wild-type ACR2 (1/12~1/3.4), which sugg

SUBMITTER: Kojima K 

PROVIDER: S-EPMC6194965 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature