A5042072364- Protein Structure and Dynamics
- Spectroscopy and Laser Applications
- Mass Spectrometry Techniques and Applications
- Spectroscopy and Quantum Chemical Studies
- Enzyme Structure and Function
- Atmospheric Ozone and Climate
- Advanced Chemical Sensor Technologies
- Scientific Measurement and Uncertainty Evaluation
- Chemical Thermodynamics and Molecular Structure
- Advanced Combustion Engine Technologies
- Photoreceptor and optogenetics research
- Advanced MEMS and NEMS Technologies
- Chemical Synthesis and Analysis
- Hemoglobin structure and function
- Optical Imaging and Spectroscopy Techniques
- Spectroscopy Techniques in Biomedical and Chemical Research
- Force Microscopy Techniques and Applications
- Atmospheric and Environmental Gas Dynamics
- Marine and coastal ecosystems
- Environmental Policies and Emissions
- Laser Applications in Dentistry and Medicine
- Calibration and Measurement Techniques
- Pharmacological Receptor Mechanisms and Effects
- Isotope Analysis in Ecology
- Lipid Membrane Structure and Behavior
University of Amsterdam
2013-2024
VSL Dutch Metrology Institute
2019-2021
Delft University of Technology
2021
Institute for Atomic and Molecular Physics
2015
Vrije Universiteit Amsterdam
2009-2011
Trp-cage is a synthetic 20-residue miniprotein which folds rapidly and spontaneously to well-defined globular structure more typical of larger proteins. Due its small size fast folding, it an ideal model system for experimental theoretical investigations protein folding mechanisms. However, Trp-cage's exact mechanism still matter debate. Here we investigate relaxation dynamics in the amide I′ spectral region (1530–1700 cm–1) using time-resolved infrared spectroscopy. Residue-specific...
Gaseous hydrogen for fuel cell electric vehicles must meet quality standards such as ISO 14687:2019 which contains maximal control thresholds several impurities could damage the cells or infrastructure. A review of analytical techniques analysis has already been carried out by Murugan et al. in 2014. Similarly, this document intends to sampling and available methods, together with a survey laboratories performing about being used. Most are addressed, however some them challenging, especially...
Salt bridges are known to play an essential role in the thermodynamic stability of folded conformation many proteins, but their influence on kinetics folding remains largely unknown. Here, we investigate effect Glu-Arg salt α-helix using temperature-jump transient-infrared spectroscopy and steady-state UV circular dichroism. We find that geometrically optimized (Glu- Arg+ spaced four peptide units apart, Glu/Arg order is such side-chain rotameric preferences favor salt-bridge formation)...
A spectroscopic depth profiling approach is demonstrated for layers of non-transparent, diffusely scattering materials. The technique based on the temporal discrimination between Raman photons emitted from surface and originating a deeper layer. Excitation was carried out with frequency-doubled, 3 ps Ti:sapphire laser system (398 nm; 76 MHz repetition rate). Time-resolved detection an intensified CCD camera that can be gated 250 gate width. performance assessed using 1 mm 2 pathlength...
Abstract Despite its wide use as a denaturant, the mechanism by which guanidinium (Gdm + ) induces protein unfolding remains largely unclear. Herein, we show evidence that Gdm can induce denaturation disrupting salt bridges stabilize folded conformation. We study ‐induced of series peptides containing Arg/Glu and Lys/Glu either or destabilize The stabilizing are found to be denatured much more efficiently than destabilizing bridges. Complementary 2D‐infrared measurements suggest in binds...
Salt bridges play an important role in protein folding and supramolecular chemistry, but they are difficult to detect characterize solution. Here, we investigate salt between glutamate (Glu(-)) arginine (Arg(+)) using two-dimensional infrared (2D-IR) spectroscopy. The 2D-IR spectrum of a salt-bridged dimer shows cross peaks the vibrational modes Glu(-) Arg(+), which provide sensitive structural probe Glu(-)⋯Arg(+) bridges. We use this β-turn locked by bridge, α-helical peptide whose...
We present a simple method to measure the dynamics of cross peaks in time-resolved two-dimensional vibrational spectroscopy. By combining suitably weighted dispersed pump-probe spectra, we eliminate diagonal contribution 2D-IR response, so that signal contains projection only onto one axes spectrum. apply investigate folding an alpha-helical peptide temperature-jump experiment and find characteristic unfolding time constants 260 ± 30 580 70 ns at 298 K.
Hydrogen fuelled vehicles can play a key role in the decarbonisation of transport and reducing emissions. To ensure durability fuel cells, specification has been developed (ISO 14687), setting upper limits to amount fraction series impurities. Demonstrating conformity with this standard requires demonstrating by measurement that actual levels impurities are below thresholds. Currently industry is unable do so, for standards sensitive dedicated analytical methods lacking. In work, we report...
Biomethane is a renewable energy gas with great potential to contribute the diversification and greening of natural supply.
Abstract Despite its wide use as a denaturant, the mechanism by which guanidinium (Gdm + ) induces protein unfolding remains largely unclear. Herein, we show evidence that Gdm can induce denaturation disrupting salt bridges stabilize folded conformation. We study ‐induced of series peptides containing Arg/Glu and Lys/Glu either or destabilize The stabilizing are found to be denatured much more efficiently than destabilizing bridges. Complementary 2D‐infrared measurements suggest in binds...
Small proteins provide good model systems for studying the fundamental forces that control protein folding. Here, we investigate folding dynamics of 28-residue zinc-finger mutant FSD-1, which is designed to form a metal-independent folded ββα-motif, and provides testing ground containing mixed α/β fold. Although FSD-1 has been actively studied, mechanism remains largely unclear. In particular, it unclear in what stage α-helix formed. To address this issue using combination...
Abstract Metrological services from National Metrology Institutes related to energy gases have been supported by the programme of key comparisons Gas Analysis Working Group Consultative Committee for Amount Substance: in Chemistry and Biology since its conception 1993. Most performed on natural gas composition measurement, which is calculation properties, thereby facilitating fiscal metering trade gas. In recent years, non-conventional substitutes, such as refinery biogas addressed. The...
To facilitate the use of biomethane in existing transmission and distribution infrastructures, CEN/TC 408 developed specifications (EN 16723) for injecting into natural gas grids using it as a transport fuel. Currently, test methods cited EN 16723 lack metrological aspects have not been specifically biomethane. address this need, ISO/TC193/SC1/WG25 “Biomethane” has created to work on standardized methods. assess conformity with specification provide essential input WG25, are being research...
Isotope ratio measurements and scale definitions are typically related to mass specectroscopy. This work discusses the challenges of optical isotope spectroscopy its prospects significantly complement spectrometry.