Mechanism-Based Tuning of a LOV Domain Photoreceptor

Journal Article · Thu Jan 01 04:00:00 EST 2009 · Nature Chemical Biology

DOI:https://doi.org/10.1038/nchembio.210· OSTI ID:1019927

Zoltowski, B; Vaccaro, B; Crane, B

Phototropin-like LOV domains form a cysteinyl-flavin adduct in response to blue light but show considerable variation in output signal and the lifetime of the photo-adduct signaling state. Mechanistic studies of the slow-cycling fungal LOV photoreceptor Vivid (VVD) reveal the importance of reactive cysteine conformation, flavin electronic environment and solvent accessibility for adduct scission and thermal reversion. Proton inventory, pH effects, base catalysis and structural studies implicate flavin N5 deprotonation as rate-determining for recovery. Substitutions of active site residues Ile74, Ile85, Met135 and Met165 alter photoadduct lifetimes by over four orders of magnitude in VVD, and similar changes in other LOV proteins show analogous effects. Adduct state decay rates also correlate with changes in conformational and oligomeric properties of the protein necessary for signaling. These findings link natural sequence variation of LOV domains to function and provide a means to design broadly reactive light-sensitive probes.

• Research Organization: Brookhaven National Laboratory (BNL) National Synchrotron Light Source
• Sponsoring Organization: DOE - OFFICE OF SCIENCE
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 1019927
• Report Number(s): BNL--95965-2011-JA
• Journal Information: Nature Chemical Biology, Journal Name: Nature Chemical Biology Journal Issue: 11 Vol. 5; ISSN 1552-4450
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ADDUCTS
CATALYSIS
CYSTEINE
DECAY
DESIGN
ISOALLOXAZINES
LIFETIME
PROBES
PROTEINS
PROTONS
RESIDUES
SOLVENTS
TUNING
national synchrotron light source