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Ultrafast fluorescence upconversion technique and its applications to proteins
- Source :
- The FEBS Journal. 282:3003-3015
- Publication Year :
- 2015
- Publisher :
- Wiley, 2015.
-
Abstract
- The basic principles and main characteristics of the ultrafast time-resolved fluorescence upconversion technique (conventional and space-resolved), including requirements for nonlinear crystals, mixing spectral bandwidth, acceptance angle, etc., are presented. Applications to flavoproteins [wild-type (WT) FMN-binding protein and its W32Y, W32A, E13R, E13K, E13Q and E13T mutants] and photoresponsive proteins [WT photoactive yellow protein and its R52Q mutant in solution and as single crystals] are demonstrated. For flavoproteins, investigations elucidating the effects of ionic charges on ultrafast electron transfer (ET) dynamics are summarized. It is shown that replacement of the ionic amino acid Glu13 and the resulting modification of the electrostatic charge distribution in the protein chromphore-binding pocket substantially alters the ultrafast fluorescence quenching dynamics and ET rate in FMN-binding protein. It is concluded that, together with donor-acceptor distances, electrostatic interactions between ionic photoproducts and other ionic groups in the proteins are important factors influencing the ET rates. In WT photoactive yellow protein and the R52Q mutant, ultrafast photoisomerization dynamics of the chromophore (deprotonated trans-p-coumaric acid) in liquid and crystal phases are investigated. It is shown that the primary dynamics in solution and single-crystal phases are quite similar; hence, the photocycle dynamics and structural differences observed at longer time scales arise mostly from the structural restraints imposed by the crystal lattice rigidity versus the flexibility in solution.
- Subjects :
- Models, Molecular
Flavoproteins
Photoisomerization
Chemistry
Static Electricity
Ionic bonding
Cell Biology
Chromophore
Photoreceptors, Microbial
Electrostatics
Photochemistry
Biochemistry
Fluorescence
Photon upconversion
Electron Transport
Crystal
Electron transfer
Spectrometry, Fluorescence
Amino Acid Substitution
Bacterial Proteins
Microscopy, Fluorescence
Point Mutation
Crystallization
Molecular Biology
Subjects
Details
- ISSN :
- 1742464X
- Volume :
- 282
- Database :
- OpenAIRE
- Journal :
- The FEBS Journal
- Accession number :
- edsair.doi.dedup.....7a6e0bef023945dee61567dd17962ded