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Shining light on rhodopsin selectivity: How do proteins decide whether to transport H+ or Cl-?

ABSTRACT: The versatile microbial rhodopsin family performs a variety of biological tasks using a highly conserved architecture, making it difficult to understand the mechanistic basis for different functions. Besaw et al. now report structures of a recently discovered cyanobacterial Cl--pumping rhodopsin and its functionally divergent mutant that reveal how these transmembrane proteins create a gradient of activity with subtle changes. These insights are paralleled by a second recent report, which in combination answers long-standing questions about rhodopsin selectivity and will facilitate future engineering efforts.

SUBMITTER: Inoue K

PROVIDER: S-EPMC7606678 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Shining light on rhodopsin selectivity: How do proteins decide whether to transport H+ or Cl-?

Inoue Keiichi K

The Journal of biological chemistry 20201001 44

The versatile microbial rhodopsin family performs a variety of biological tasks using a highly conserved architecture, making it difficult to understand the mechanistic basis for different functions. Besaw et al. now report structures of a recently discovered cyanobacterial Cl--pumping rhodopsin and its functionally divergent mutant that reveal how these transmembrane proteins create a gradient of activity with subtle changes. These insights are paralleled by a second recent re ...[more]

PMID: 33127867

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