Raman Optical Activity of Retinal Chromophore in Sensory Rhodopsin II.
Kouhei NishikawaRyosuke KuroiwaJun TamogamiMasashi UnnoTomotsumi FujisawaPublished in: The journal of physical chemistry. B (2023)
Raman optical activity (ROA) spectroscopy was used to study the conformation of the retinal chromophore in sensory rhodopsin II (SRII), which is a blue-green light sensor of microbes. The ROA spectrum consisted of the negative vibrational bands of the chromophore, whose relative intensities are similar to those of the parent Raman spectrum. This spectral feature was explained by the left-handed helical twist of the retinal chromophore on the basis of quantum chemical calculations. On the other hand, we found that the chromophore conformation based on the crystal structures of SRII has a right-handed helical twist, which does not agree with the observation. This specific result suggests that the consistency with chiro-optical properties can be a key criterion for the accurate prediction and/or evaluation of chromophore conformation in retinal-binding proteins.
Keyphrases
- optical coherence tomography
- diabetic retinopathy
- molecular dynamics simulations
- high resolution
- optic nerve
- epithelial mesenchymal transition
- density functional theory
- molecular dynamics
- raman spectroscopy
- machine learning
- high speed
- magnetic resonance
- deep learning
- single molecule
- signaling pathway
- mass spectrometry
- energy transfer
- monte carlo