title: Photochemistry of flavoprotein light sensors.
abstract: Three major classes of flavin photosensors, light oxygen voltage (LOV) domains, blue light sensor using FAD (BLUF) proteins and cryptochromes (CRYs), regulate diverse biological activities in response to blue light. Recent studies of structure, spectroscopy and chemical mechanism have provided unprecedented insight into how each family operates at the molecular level. In general, the photoexcitation of the flavin cofactor leads to changes in redox and protonation states that ultimately remodel protein conformation and molecular interactions. For LOV domains, issues remain regarding early photochemical events, but common themes in conformational propagation have emerged across a diverse family of proteins. For BLUF proteins, photoinduced electron transfer reactions critical to light conversion are defined, but the subsequent rearrangement of hydrogen bonding networks key for signaling remains highly controversial. For CRYs, the relevant photocycles are actively debated, but mechanistic and functional studies are converging. Despite these challenges, our current understanding has enabled the engineering of flavoprotein photosensors for control of signaling processes within cells.
authors.affiliation: Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, USA.
authors.forename: Karen S
authors.identifier: 0000000330482226
authors.initials: KS
authors.lastname: Conrad
authors.affiliation: Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, USA.
authors.forename: Craig C
authors.initials: CC
authors.lastname: Manahan
authors.affiliation: Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, USA.
authors.forename: Brian R
authors.initials: BR
authors.lastname: Crane
mesh_terms: D056931:Cryptochromes / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004579:Electron Transport; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D005182:Flavin-Adenine Dinucleotide / Q000737:chemistry* / Q000378:metabolism; D015870:Gene Expression; D006860:Hydrogen Bonding; D008027:Light; D008958:Models, Molecular; D010084:Oxidation-Reduction; D010727:Phosphoric Diester Hydrolases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D055668:Photochemical Processes; D015202:Protein Engineering; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary
chemical_list: D056931:Cryptochromes; D029968:Escherichia coli Proteins; D005182:Flavin-Adenine Dinucleotide; D010727:Phosphoric Diester Hydrolases; C510176:bluF protein, E coli