Structural basis for the prolonged photocycle of sensory rhodopsin II revealed by serial synchrotron crystallography.

ABSTRACT: Microbial rhodopsins form a diverse family of light-sensitive seven-transmembrane helix retinal proteins that function as active proton or ion pumps, passive light-gated ion channels, and photosensors. To understand how light-sensing in archaea is initiated by sensory rhodopsins, we perform serial synchrotron X-ray crystallography (SSX) studies of light induced conformational changes in sensory rhodopsin II (NpSRII) from the archaea Natronomonas pharaonis, both collecting time-resolved SSX data and collecting SSX data during continuous illumination. Comparing light-induced electron density changes in NpSRII with those reported for bacteriorhodopsin (bR) reveals several common light-induced structural perturbations. Unlike bR, however, helix G of NpSRII does not unwind near the conserved ly

SUBMITTER: Bosman R 

PROVIDER: S-EPMC11992208 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature