Biophysical characterization of microbial rhodopsins with DSE motif.

ABSTRACT: Microbial rhodopsins are photoreceptive transmembrane proteins that transport ions or regulate other intracellular biological processes. Recent genomic and metagenomic analyses found many microbial rhodopsins with unique sequences distinct from known ones. Functional characterization of these new types of microbial rhodopsins is expected to expand our understanding of their physiological roles. Here, we found microbial rhodopsins having a DSE motif in the third transmembrane helix from members of the Actinobacteria. Although the expressed proteins exhibited blue-green light absorption, either no or extremely small outward H⁺ pump activity was observed. The turnover rate of the photocycle reaction of the purified proteins was extremely slow compared to typical H⁺ pumps

SUBMITTER: Marin MDC 

PROVIDER: S-EPMC10865882 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature