Tilo Mathes

Tilo Mathes
ResearchGate | RG · Product Management

PhD
Interested in photobiotechnological applications for a circular economy

About

56
Publications
27,985
Reads
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1,298
Citations
Introduction
I'm interested in the molecular dynamics of biological systems. For this purpose I studied biological photoreceptor proteins. Due to their function as signalling proteins their structure can be perturbed by a flash of light and monitored spectroscopically with time resolution down to the femtosecond time domain.
Additional affiliations
January 2015 - March 2015
Nagoya Institute of Technology
Position
  • Visiting Associate Professor
Description
  • FTIR spectroscopic investigation of light-induced DNA repair
March 2011 - October 2015
Vrije Universiteit Amsterdam
Position
  • Researcher
Description
  • Time resolved spectroscopy on sensory photoreceptors
January 2008 - February 2011
Humboldt-Universität zu Berlin
Position
  • PostDoc Position
Description
  • Customized expression systems; in vivo reconstitution of flavoproteins
Education
July 2004 - December 2007
Humboldt-Universität zu Berlin
Field of study
  • Biophysics
September 1999 - April 2000
Brock University
Field of study
  • Organic synthesis
October 1997 - February 2004
University of Freiburg
Field of study
  • Biochemistry

Publications

Publications (56)
Article
Full-text available
UVR8 is a novel UV-B photoreceptor that regulates a range of plant responses and is already used as a versatile optogenetic tool. Instead of an exogenous chromophore, UVR8 uniquely employs tryptophan side chains to accomplish UV-B photoreception. UV-B absorption by homo-dimeric UVR8 induces monomerization and hence signaling, but the underlying pho...
Article
Full-text available
The structural changes that facilitate signal transduction in blue light sensors using FAD (BLUF) photoreceptors and confer the stability of the rearranged hydrogen bond network between flavin and protein in the signaling state are still poorly understood. Here, we investigate a semiconserved Trp residue in SyPixD (Slr1694) by isotope-edited vibrat...
Article
Full-text available
Biological reactions are facilitated by delicate molecular interactions between proteins, cofactors and substrates. To study and understand their dynamic interactions researchers have to take great care not to influence or distort the object of study. As a non-invasive alternative to a site-directed mutagenesis approach, selective isotope labeling...
Article
Full-text available
Algae, plants, bacteria, and fungi contain flavin-binding light-oxygen-voltage (LOV) domains that function as blue light sensors to control cellular responses to light. In the second LOV domain of phototropins, called LOV2 domains, blue light illumination leads to covalent bond formation between protein and flavin that induces the dissociation and...
Preprint
Full-text available
Algae, plants, bacteria and fungi contain flavin binding Light-Oxygen-Voltage (LOV) domains that function as blue light sensors to control cellular responses to light. In the second LOV domain of phototropins, called LOV2 domains, blue light illumination leads to covalent bond formation between protein and flavin that induces the dissociation and u...
Article
Full-text available
Channelrhodopsin (ChR) is a key protein of the optogenetic toolkit. C1C2, a functional chimeric protein of Chlamydomonas reinhardtii ChR1 and ChR2, is the only ChR whose crystal structure has been solved, and thus uniquely suitable for structure-based analysis. We report C1C2 photoreaction dynamics with ultrafast transient absorption and multi-puls...
Article
Plant cryptochromes are photoreceptors that regulate flowering, circadian rhythm and photomorphogenesis in response to blue and UV-A light. It has been demonstrated that the oxidized flavin cofactor is photoreduced to the neutral radical state via separate electron and proton transfer. Conformational changes have been found in the C-terminal extens...
Article
Full-text available
The two Light, Oxygen, and Voltage domains of phototropin are blue-light photoreceptor domains which control various functions in plants and green algae. The key step of the light-driven reaction is the formation of a photoadduct between its FMN chromophore and a conserved cysteine, where the canonical reaction proceeds through the FMN triplet stat...
Article
Full-text available
Light-triggered reactions of biological photoreceptors have gained immense attention for their role as molecular switches in their native organisms and for optogenetic application. The LOV2 domain of plant phototropin binds a C-terminal Jα helix that is docked on a β-sheet and unfolds upon light absorption by the FMN chromophore. In this report, th...
Chapter
Photoreceptors are found in all kingdoms of life and mediate crucial responses to environmental challenges. Nature has evolved various types of photoresponsive protein structures with different chromophores and signaling concepts for their given purpose. The abundance of these signaling proteins as found nowadays by (meta-)genomic screens enriched...
Article
Full-text available
The resting and signaling structures of the blue-light sensing using flavin (BLUF) photoreceptor domains are still controversially debated due to differences in the molecular models obtained by crystal and NMR structures. Photocycles for the given preferred structural framework have been established, but a unifying picture combining experiment and...
Article
Blue light receptors using FAD (BLUF) facilitate blue light induced signal transduction via a light induced rearrangement of hydrogen bonds between the flavin chromophore and a conserved glutamine side chain. Here, we investigated the photochemistry of the BLUF domain Slr1694 from Synechocystis sp. in which the glutamine side chain was removed. Wit...
Article
Full-text available
A bacteriophytochrome from Stigmatella aurantiaca is an unusual member of the bacteriophytochrome family that is devoid of hydrogen bonding to the carbonyl group of ring D of the biliverdin (BV) chromophore. The photodynamics of BV in SaBphP1 wild type and the single mutant T289H reintroducing hydrogen bonding to ring D show that the strength of th...
Article
Full-text available
Automation can vastly reduce the cost of experimental labor and thus facilitate high experimental throughput, but little off-the-shelf hardware for the automation of illumination experiments is commercially available. Here, we use inexpensive open-source electronics to add programmable illumination capabilities to a multimode microplate reader. We...
Article
Full-text available
Tryptophan residues at the dimer interface of the plant photoreceptor UVR8 promote monomerisation after UV-B absorption via a so far unknown mechanism. Using FTIR spectroscopy we assign light-induced structural transitions of UVR8 mainly to amino acid side chains without major transformations of the secondary structure of the physiologically releva...
Article
Observations of light-receptive enzyme complexes are usually complicated by simultaneous overlapping signals from the chromophore, apo-protein, and substrate, so that only the initial, ultrafast, photon-chromophore reaction, and the final, slow, protein conformational change provide separate, non-overlapping signals. Each provides its own advantage...
Article
Photoactivated adenylyl cyclases are powerful tools for optogenetics and to investigate signal transduction mechanisms in biological photoreceptors. Due to its strong increase in enzyme activity in the light the BLUF (blue light sensor using FAD) activated adenylyl cyclase bPAC from Beggiatoa sp. is a highly attractive model system to study BLUF do...
Article
Full-text available
Flavin-binding photoreceptor proteins use the isoalloxazine moiety of flavin cofactors to absorb light in the blue/UV-A wavelength region and subsequently translate it into biological information. The underlying photochemical reactions and protein structural dynamics are delicately tuned by the protein environment and represent fundamental reaction...
Article
Full-text available
Laser pulse nonlinear transmission measurements through saturable absorbers of known absorp-tion parameters allow the measurement of their energy density. On the other hand, nonlinear transmission measurements of laser pulses of known energy density through absorbing media al-low their absorption parameter determination. The peak energy density w 0...
Article
The photo-dynamics of the recombinant rhodopsin fragment of the histidine kinase rhodopsin HKR1 from Chlamydomonas reinhardtii was studied by absorption and fluorescence spectroscopy. The retinal cofactor of HKR1 exists in two Schiff base forms RetA and RetB. RetA is the deprotonated 13-cis retinal Schiff base absorbing in the UVA spectral region....
Article
Full-text available
Most biological photoreceptors are protein/cofactor complexes that induce a physiological reaction upon absorption of a photon. Therefore, these proteins represent signal converters that translate light into biological information. Researchers use this property to stimulate and study various biochemical processes conveniently and non-invasively by...
Article
Full-text available
The riboflavin analog roseoflavin is an antibiotic produced by Streptomyces davawensis. Riboflavin transporters are responsible for roseoflavin uptake by target cells. Roseoflavin is converted to the flavin mononucleotide (FMN) analog roseoflavin mononucleotide (RoFMN) by flavokinase and to the flavin adenine dinucleotide (FAD) analog roseoflavin a...
Article
Full-text available
Rhodopsins are light-activated chromoproteins that mediate signaling processes via transducer proteins or promote active or passive ion transport as ion pumps or directly light-activated channels. Here, we provide spectroscopic characterization of a rhodopsin from the Chlamydomonas eyespot. It belongs to a recently discovered but so far uncharacter...
Article
Full-text available
Photoinduced electron transfer in biological systems, especially in proteins, is a highly intriguing matter. Its mechanistic details cannot be addressed by structural data obtained by crystallography alone because this provides only static information on a given redox system. In combination with transient spectroscopy and site-directed manipulation...
Conference Paper
Full-text available
UV/visible pump, mid-IR probe spectroscopy measurements based on the chirped upconversion method were expanded to the frequency region below 1800cm −1 with the nonlinear optical crystal AgGaGeS 4 . Pump-probe experiments were demonstrated with GaAs and the photoreceptor protein Slr1694.
Article
BLUF domains are flavin-binding photoreceptors that can be reversibly switched from a dark-adapted state to a light-adapted state. Proton-coupled electron transfer (PCET) from a conserved tyrosine to the flavin that results in a neutral flavin semiquinone/tyrosyl radical pair constitutes the photoactivation mechanism of BLUF domains. Whereas in the...
Article
Full-text available
Broadband femtosecond mid-infrared pulses can be converted into the visible spectral region by chirped pulse upconversion. We report here the upconversion of pump probe transient signals in the frequency region below 1800cm(-1), using the nonlinear optical crystal AgGaGeS4, realizing an important expansion of the application range of this method. E...
Article
The BlrB protein from Rhodobacter sphaeroides is a small 136 amino acid photoreceptor belonging to the BLUF family of blue light receptors. It contains merely the conserved BLUF fold responsible for binding the flavin pigment and a short C-terminal extension of unknown function. We investigated the primary photoreactions of BlrB by picosecond fluor...
Conference Paper
The wild-type phototropin protein phot from the green alga Chlamydomonas reinhardtii consists of two N-terminal LOV domains LOV1 and LOV2 with flavin mononucleotide (FMN) cofactor and a C-terminal serine-threonine kinase domain. It controls multiple steps in the sexual lifecycle of the alga. Here the LOV1-His domain of phot with modified cofactor i...
Article
Blue-light sensitive photoreceptory BLUF domains are flavoproteins, which regulate various, mostly stress-related processes in bacteria and eukaryotes. The photoreactivity of the flavin adenine dinucleotide (FAD) cofactor in three BLUF domains from Rhodobacter sphaeroides, Synechocystis sp. PCC 6803 and Escherichia coli have been studied at low tem...
Article
The wild-type phototropin protein phot from the green alga Chlamydomonas reinhardtii with the blue-light photoreceptor domains LOV1 and LOV2 has flavin mononucleotide (FMN) as cofactor. For the LOV1-His domain from phot of C. reinhardtii studied here, the FMN chromophore was replaced by roseoflavin monophosphate (8-dimethylamino-8-demethyl-FMN, RoF...
Article
Exploring protein-cofactor interactions on a molecular level is one of the major challenges in modern biophysics. Based on structural data alone it is rarely possible to identify how subtle interactions between a protein and its cofactor modulate the protein's reactivity. In the case of enzymatic processes in which paramagnetic molecules play a cer...
Article
An absorption and emission spectroscopic characterization of roseoflavin (8-dimethylamino-8-demethylriboflavin, RoF) in aqueous solutions was carried out. The studies were concentrated on roseoflavin in pH 8 phosphate buffer. Absorption cross-section spectra, fluorescence excitation spectra, fluorescence quantum distributions, fluorescence quantum...
Article
The blue-light photoreceptor phototropin plays a crucial role in optimizing photosynthesis in plants. In the two light-, oxygen-, or voltage-sensitive (LOV) domains of phototropin, the light stimulus is absorbed by the flavin chromophores. The signal is assumed to be transferred via dissociation and unfolding of a conserved J alpha helix element to...
Article
BLUF (blue light sensing using FAD) domains belong to a novel group of blue light sensing receptor proteins found in microorganisms. We have assessed the role of specific aromatic and polar residues in the Synechocystis Slr1694 BLUF protein by investigating site-directed mutants with substitutions Y8W, W91F, and S28A. The W91F and S28A mutants form...
Article
The wild-type BLUF protein Slr1694 from Synechocystis sp. PCC6803 (BLUF=blue-light sensor using FAD) has flavin adenosine dinucleotide (FAD) as natural cofactor. This light sensor causes positive phototaxis of the marine cyanobacterium. In this study the FAD cofactor of the wild-type Slr1694 was replaced by roseoflavin (RoF) and the roseoflavin der...
Article
Roseoflavin (8-dimethylamino-8-demethyl-D-riboflavin) and riboflavin in aqueous and organic solvents are studied by optical absorption spectroscopy, fluorescence spectroscopy, and fluorescence decay kinetics. Solvent polarity dependent absorption shifts are observed. The fluorescence quantum yields are solvent dependent. For roseoflavin the fluores...
Article
The flavin dye 8-amino-8-demethyl-D-riboflavin (AF) in the solvents water, DMSO, methanol, and chloroform/DMSO was studied by absorption and fluorescence spectroscopy. The first absorption band is red-shifted compared to riboflavin, and blue-shifted compared to roseoflavin (8-dimethylamino-8-demethyl-D-riboflavin). The fluorescence quantum yield of...
Article
To understand flavoprotein mechanisms and reactivity, biochemical and biophysical methods are usually employed, and differences between wild-type and mutated proteins with altered primary structures are placed under specific consideration. Alternatively, the cofactor can be modified, and modified flavoproteins can be studied accordingly. Here we pr...
Article
BLUF domains constitute a recently discovered class of photoreceptor proteins found in bacteria and eukaryotic algae. BLUF domains are blue-light sensitive through a FAD cofactor that is involved in an extensive hydrogen-bond network with nearby amino acid side chains, including a highly conserved tyrosine and glutamine. The participation of partic...
Thesis
Full-text available
Die lichtaktivierte Kinase Phototropin aus Chlamydomonas reinhardtii, die photoaktivierte Adenylatcyclase (PAC) aus Euglena gracilis und das BLUF-Protein Slr1694 aus Synechocystis sp. PCC 6803 wurden in Hinblick auf die molekularen Details der primären photochemischen Prozesse sowie der Signalweiterleitung untersucht. Phototropin wurde mit Hilfe vo...
Article
The photo-cycle dynamics of the H44R mutant of the BLUF domain of the transcriptional anti-repressor protein AppA (AppA-H44R) from the non-sulfur anoxyphototropic purple bacterium Rhodobacter sphaeroides is studied in order to gain information on the involvement of His44 in the photo-cyclic mechanism of the AppA BLUF domain and to add information t...
Article
The BLUF protein Slr1694 from the cyanobacterium Synechocystis sp. PCC6803 is characterized by absorption and emission spectroscopy. Slr1694 expressed from E. coli which non-covalently binds FAD, FMN, and riboflavin (called Slr1694(I)), and reconstituted Slr1694 which dominantly contains FAD (called Slr1694(II)) are investigated. The receptor confo...

Questions

Question (1)
Question
I'm looking for an open repository or culture collection to deposit some genetically engineered E. coli strains (from the papers below). The primary goal is to preserve those strains for the long term future and provide easy and ideally free access for researchers all over the world.
Please post any recommendations and experiences with such service providers here.

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Projects

Projects (2)
Archived project
In this project we investigate the very first steps of an intriguing photoprotection mechanism in plants that is conveyed by the WD40 protein UVR8. We use ultrafast molecular spectroscopy to investigate how UV-B induces structural changes in the plant photoreceptor UVR8.
Archived project
In this project we worked on establishing isotope labelling strategies for photoreceptor proteins that employ flavin as a pigment. We created an extensive collection of genetically modified Escherichia coli strains that are suitable for high level expression and amino-acid and flavin cofactor selective isotope or chemical labelling.