Time-Resolved X-Ray Solution Scattering Reveals the Structural Photoactivation of a Light-Oxygen-Voltage Photoreceptor

• Published in: Structure (London) 2017-06, Vol.25 (6), p.933-938.e3
• Main Authors: Berntsson, Oskar, Diensthuber, Ralph P., Panman, Matthijs R., Björling, Alexander, Hughes, Ashley J., Henry, Léocadie, Niebling, Stephan, Newby, Gemma, Liebi, Marianne, Menzel, Andreas, Henning, Robert, Kosheleva, Irina, Möglich, Andreas, Westenhoff, Sebastian
• Format: Article
• Language: English
• Subjects: Bacillus subtilis - chemistry; bacillus-subtilis; Bacterial Proteins - chemistry; Bacterial Proteins - metabolism; Biochemistry and Molecular Biology; Biokemi och molekylärbiologi; biological macromolecules; Cell Biology; Cellbiologi; flavoprotein; Light-oxygen-voltage; lov2 domains; Models, Molecular; Molecular Dynamics Simulation; photocycle; Photoreceptors, Microbial - chemistry; Photoreceptors, Microbial - metabolism; phototropin; protein; Protein Domains; protein structural dynamics; receptor; Scattering, Radiation; sensor histidine kinase; sensory photoreceptor; Signal Transduction; transduction; X-ray solution scattering; X-Rays; ytva
• ISSN: 0969-2126; 1878-4186
• DOI: 10.1016/j.str.2017.04.006

Light-oxygen-voltage (LOV) receptors are sensory proteins controlling a wide range of organismal adaptations in multiple kingdoms of life. Because of their modular nature, LOV domains are also attractive for use as optogenetic actuators. A flavin chromophore absorbs blue light, forms a bond with a proximal cysteine residue, and induces changes in the surroundings. There is a gap of knowledge on how this initial signal is relayed further through the sensor to the effector module. To characterize these conformational changes, we apply time-resolved X-ray scattering to the homodimeric LOV domain from Bacillus subtilis YtvA. We observe a global structural change in the LOV dimer synchronous with the formation of the chromophore photoproduct state. Using molecular modeling, this change is identified as splaying apart and relative rotation of the two monomers, which leads to an increased separation at the anchoring site of the effector modules. [Display omitted] •Time-resolved X-ray solution scattering reveals structure of a LOV signaling state•Signaling state formation is synchronous with chromophore photoproduct formation•LOV domain signaling state is characterized by splaying apart of the LOV dimer In this study Berntsson et al. have used time-resolved X-ray solution scattering and molecular modeling to characterize light-induced conformational rearrangements in the light-oxygen-voltage photosensory domain from Bacillus subtilis YtvA.