A structural model for the full-length blue light-sensing protein YtvA from Bacillus subtilis, based on EPR spectroscopy

Engelhard, Christopher; Raffelberg, Sarah; Tang, Yifen; Diensthuber, Ralph P.; Möglich, Andreas; Losi, Aba; Gärtner, Wolfgang; Bittl, Robert

doi:10.1039/c3pp50128k

Cited by 13 publications

(19 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Replacement of the conserved cysteine 62 by alanine prevents the formation of the cysteinyl-C4a-adduct, but allows photoreduction of flavin to the neutral semiquinone (NSQ) radical upon illumination 27 . The NSQ radical can then be used as an intrinsic spin probe for distance measurements 12, 28, 29 . As the spin density is mainly centred on the N5 and C4a atoms of flavin 30, 31 , corresponding ELDOR experiments generally yield narrow distance distributions not prone to the positional uncertainty introduced by the flexibility of the extrinsic MTS spin label.…”

Section: Resultsmentioning

confidence: 99%

Blue-light reception through quaternary transitions

Engelhard

Diensthuber

Möglich

et al. 2017

Sci Rep

Self Cite

View full text Add to dashboard Cite

Sensory photoreceptors absorb light via their photosensor modules and trigger downstream physiological adaptations via their effector modules. Light reception accordingly depends on precisely orchestrated interactions between these modules, the molecular details of which often remain elusive. Using electron-electron double resonance (ELDOR) spectroscopy and site-directed spin labelling, we chart the structural transitions facilitating blue-light reception in the engineered light-oxygen-voltage (LOV) histidine kinase YF1 which represents a paradigm for numerous natural signal receptors. Structural modelling based on pair-wise distance constraints derived from ELDOR pinpoint light-induced rotation and splaying apart of the two LOV photosensors in the dimeric photoreceptor. Resultant molecular strain likely relaxes as left-handed supercoiling of the coiled-coil linker connecting sensor and effector units. ELDOR data on a photoreceptor variant with an inverted signal response indicate a drastically altered dimer interface but light-induced structural transitions in the linker that are similar to those in YF1. Taken together, we provide mechanistic insight into the signal trajectories of LOV photoreceptors and histidine kinases that inform molecular simulations and the engineering of novel receptors.

show abstract

Section: Resultsmentioning

confidence: 99%

Blue-light reception through quaternary transitions

Engelhard

Diensthuber

Möglich

et al. 2017

Sci Rep

Self Cite

View full text Add to dashboard Cite

show abstract

“…Dimeric YtvA has subunits associated through hydrophobic contacts on the LOV β-sheet, but instead of the Jα helix flanking the LOV β–scaffold, it extends from the LOV core to form a pseudo-coiled coil arrangement with the opposing subunit 29,30 . In full length YtvA, interactions in the coupled STAS domain also stabilize dimerization 31,32 . Structural studies on the dark and light-adapted states of the YtvA LOV domain suggest a rotation of the two monomers by 4–5° relative to one another 5,6 , consistent with little conformational change in the full-length protein observed by dipolar ESR studies 39 .…”

Section: Lov Domainsmentioning

confidence: 99%

Photochemistry of flavoprotein light sensors

Conrad¹,

Manahan²,

Crane³

2014

Nat Chem Biol

205

234

View full text Add to dashboard Cite

Three major classes of flavin photosensors, LOV domains, BLUF proteins and cryptochromes 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 remain highly controversial. For cryptochromes, 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.

show abstract

“…The structure of YF1 is homodimeric, dominated by a dimerization between two LOV domains of adjacent proteins. Such LOV‐directed homodimer formation has also been postulated for full‐length YtvA, carrying a LOV and a STAS domain, making the structure of YF1 a likely candidate for structural modeling of LG1 . LG1 bears the same YtvA‐LOV domain, including regions flanking the LOV core, i.e.…”

Section: Resultsmentioning

confidence: 84%

FRET in a Synthetic Flavin‐ and Bilin‐binding Protein

Simon

Losi

Zhao

et al. 2017

Photochem & Photobiology

Self Cite

View full text Add to dashboard Cite

The last decade has seen development and application of a large number of novel fluorescence-based techniques that have revolutionized fluorescence microscopy in life sciences. Preferred tags for such applications are genetically encoded fluorescent proteins (FP), mostly derivatives of the green fluorescent protein (GFP). Combinations of FPs with wavelength-separated absorption/fluorescence properties serve as excellent tools for molecular interaction studies, for example, protein-protein complexes or enzyme-substrate interactions, based on the FRET phenomenon (Förster resonance energy transfer). However, alternatives are requested for experimental conditions where FP proteins or FP couples are not or less efficiently applicable. We here report as a "proof of principle" a specially designed, non-naturally occurring protein (LG1) carrying a combination of a flavin-binding LOV- and a photochromic bilin-binding GAF domain and demonstrate a FRET process between both chromophores.

show abstract

A structural model for the full-length blue light-sensing protein YtvA from Bacillus subtilis, based on EPR spectroscopy

Cited by 13 publications

References 38 publications

Blue-light reception through quaternary transitions

Blue-light reception through quaternary transitions

Photochemistry of flavoprotein light sensors

FRET in a Synthetic Flavin‐ and Bilin‐binding Protein

Contact Info

Product

Resources

About