A5015329154- Protein Structure and Dynamics
- Enzyme Structure and Function
- Spectroscopy and Quantum Chemical Studies
- Photoreceptor and optogenetics research
- Mass Spectrometry Techniques and Applications
- Lipid Membrane Structure and Behavior
- Photochemistry and Electron Transfer Studies
- Chemical Synthesis and Analysis
- DNA and Nucleic Acid Chemistry
- Antimicrobial Peptides and Activities
- Luminescence and Fluorescent Materials
- Supramolecular Self-Assembly in Materials
- RNA and protein synthesis mechanisms
- Molecular Junctions and Nanostructures
- Photosynthetic Processes and Mechanisms
- RNA Interference and Gene Delivery
- Photochromic and Fluorescence Chemistry
- Molecular Sensors and Ion Detection
- Advanced Fluorescence Microscopy Techniques
- Click Chemistry and Applications
- Glycosylation and Glycoproteins Research
- Cell Adhesion Molecules Research
- Advanced biosensing and bioanalysis techniques
- Molecular spectroscopy and chirality
- Hemoglobin structure and function
Peking University
2014-2025
Beijing National Laboratory for Molecular Sciences
2014-2025
King University
2025
University of Pennsylvania
2013-2022
California University of Pennsylvania
2006-2021
Philadelphia University
2015-2021
Optica
2014-2018
Laboratoire de physique des lasers
2015-2018
Optical Sciences (United States)
2017
Soochow University
2016
Significance The ability of trimethylamine N-oxide (TMAO) to counteract osmotic stress along with the deleterious effects denaturants such as urea is fascinating and has inspired many studies. To further our understanding how TMAO acts stabilize folded proteins, we carry out an infrared experiment designed probe microscopic details this action explicitly from perspective solute molecule. Our results reveal that protein-stabilizing effect originates two contributions: One entropic other...
It is well-known that the C⋮N stretching vibration in acetonitrile sensitive to solvent. Therefore, we proposed this contribution use vibrational mode report local environment of a particular amino acid proteins or environmental changes upon binding folding. We have studied solvent-induced frequency shift two nitrile-derivatized acids, which are, AlaCN and PheCN, H2O tetrahydrofuran (THF), respectively. Here, THF was used approximate protein's hydrophobic interior because its low dielectric...
The helix-coil transition kinetics of an α-helical peptide were investigated by time-resolved infrared spectroscopy coupled with laser-induced temperature-jump initiation method. Specific isotope labeling the amide carbonyl groups 13 C at selected residues was used to obtain site-specific information. relaxation following a temperature jump, obtained probing I′ band backbone, exhibit nonexponential behavior and are sensitive both initial final temperatures. These data consistent conformation...
Both turn sequence and interstrand hydrophobic side-chain–side-chain interaction have been suggested to be important determinants of β-hairpin stability. However, their roles in controlling the folding dynamics β-hairpins not clearly determined. Herein, we investigated structural stability kinetics a series tryptophan zippers by static IR CD spectroscopies temperature jump method. Our results support mechanism wherein rate-limiting event corresponds formation turn. We find that logarithm...
The primary events in the all- trans to 13- cis photoisomerization of retinal bacteriorhodopsin have been investigated with femtosecond time-resolved absorbance spectroscopy. Spectra measured over a broad range extending from 7000 22,400 cm −1 reveal features whose dynamics are inconsistent model proposed earlier account for highly efficient process. Emerging this work is new three-state model. Photoexcitation visible light accesses shallow well on excited state potential energy surface....
We studied the microsecond folding dynamics of three β hairpins (Trp zippers 1–3, TZ1–TZ3) by using temperature-jump fluorescence and atomistic molecular in implicit solvent. In addition, we TZ2 time-resolved IR spectroscopy. By distributed computing, obtained an aggregate simulation time 22 ms. The simulations included 150, 212, 48 events at room temperature for TZ1, TZ2, TZ3, respectively. all-atom optimized potentials liquid (OPLS aa ) potential set predicted TZ1 properties well;...
Cell-derived GPMVs (giant plasma-membrane vesicles) enable investigation of lipid phase separation in a system with appropriate biological complexity under physiological conditions, and the present study were used to investigate cholesterol-dependence domain formation stability. The cholesterol level is directly related abundance liquid-ordered fraction, which majority vesicles from untreated cells. Miscibility transition temperature depends on correlates strongly presence...
Elucidating the underlying molecular mechanisms of protein folding and function is a very exciting active research area, but poses significant challenges. This due in part to fact that existing experimental techniques are incapable capturing snapshots along 'reaction coordinate' question with both sufficient spatial temporal resolutions. In this regard, recent years have seen increased interests efforts development employment site-specific probes enhance structural sensitivity spectroscopic...
Polyphosphoinositides (PPIs) and in particular phosphatidylinositol-(4,5)-bisphosphate (PI4,5P2), control many cellular events bind with variable levels of specificity to hundreds intracellular proteins vitro. The much more restricted targeting PPIs cell membranes is thought result part from the formation spatially distinct PIP2 pools, but mechanisms that cause maintenance clusters are still under debate. hypothesis forms submicrometer-sized membrane by electrostatic interactions divalent...
Many fluorescent proteins are currently available for biological spectroscopy and imaging measurements, allowing a wide range of biochemical biophysical processes interactions to be studied at various length scales. However, in applications where small fluorescence reporter is required or desirable, the choice fluorophores rather limited. As such, continued effort has been devoted development amino acid-based that do not require specific environment additional time mature have large quantum...
Since the building blocks of DNA are nonfluorescent, various external fluorescence reporters have been employed to investigate structure, dynamics, and function G‐quadruplexes (GQs) i‐motifs (iMs), which play an important role in gene regulation expression. However, most those lack ability provide site‐specific structural information interest. Therefore, it is necessary develop fluorescent nucleoside analogues that can be covalently inserted into oligonucleotides, not only serve this...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTInfrared Studies of Fast Events in Protein FoldingR. Brian Dyer, Feng Gai, William H. Woodruff, Rudolf Gilmanshin, and Robert CallenderView Author Information Chemical Science Technology Division, CST-4, Mail Stop J586, Los Alamos National Laboratory, Alamos, New Mexico 87545 Department Biochemistry, Albert Einstein College Medicine, 1300 Morris Park Avenue, Bronx, York 10461 Cite this: Acc. Chem. Res. 1998, 31, 11, 709–716Publication Date...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTFluorescent species of 7-azaindole and 7-azatryptophan in waterY. Chen, R. L. Rich, F. Gai, J. W. PetrichCite this: Phys. Chem. 1993, 97, 9, 1770–1780Publication Date (Print):March 1, 1993Publication History Published online1 May 2002Published inissue 1 March 1993https://pubs.acs.org/doi/10.1021/j100111a011https://doi.org/10.1021/j100111a011research-articleACS PublicationsRequest reuse permissionsArticle Views837Altmetric-Citations141LEARN ABOUT...
Here, we describe the folding/unfolding kinetics of α 3 D, a small designed three-helix bundle. Both IR temperature jump and ultrafast fluorescence mixing methods reveal single-exponential process consistent with minimal folding time 3.2 ± 1.2 μs (at ≈50°C), indicating that protein can fold on 1- to 5-μs scale. Furthermore, nature relaxation indicates prefactor for transition state (TS)-folding models is probably ≥1 (μs) –1 this size topology. Molecular dynamics simulations spectroscopy...
The helix−coil transition of a synthetic α-helical peptide (the d-Arg peptide), Ac-YGG(KAAAA)3-CO-d-Arg-CONH2, was studied by static far-UV circular dichroism (CD) and time-resolved infrared spectroscopy coupled with the laser-induced temperature-jump technique for rapid relaxation initiation. Equilibrium thermal unfolding measurements monitored CD reveal an apparent two-state transition, melting temperature around 10 °C. Time-resolved (IR) following jump, however, biphasic (or multiphasic)...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSolvation of 7-azaindole in alcohols and water: evidence for concerted, excited-state, double-proton transfer alcoholsY. Chen, F. Gai, J. W. PetrichCite this: Am. Chem. Soc. 1993, 115, 22, 10158–10166Publication Date (Print):November 1, 1993Publication History Published online1 May 2002Published inissue 1 November 1993https://pubs.acs.org/doi/10.1021/ja00075a035https://doi.org/10.1021/ja00075a035research-articleACS PublicationsRequest reuse...
2D IR spectroscopy was used to probe the hydrophobic core structure of 35-residue Villin headpiece subdomain, HP35, by monitoring C≡N vibrational stretching band a cyano substituted phenylalanine (Phe). The presence two humps in frequency distribution folded equilibrium state is revealed. They represent states that exchange more slowly than ca. 10 ps. CN stretch mode peak frequencies (and their populations) are 2228.7 (44%) and 2234.5 cm(-1) (56%). modes have different frequency-frequency...
The ability to quantify the local electrostatic environment of proteins and protein/peptide assemblies is key gaining a microscopic understanding many biological interactions processes. Herein, we show that ester carbonyl stretching vibration two non-natural amino acids, L-aspartic acid 4-methyl L-glutamic 5-methyl ester, convenient sensitive probe in this regard, since its frequency correlates linearly with field for both hydrogen-bonding non-hydrogen-bonding environments. We expect...
Recent theories of protein folding suggest that individual proteins within a large ensemble may follow different routes in conformation space from the unfolded state toward native and vice versa. Herein, we introduce new type kinetics experiment shows how unfolding pathways can be selected by varying initial reaction conditions. The relaxation major cold shock Escherichia coli (CspA) response to laser-induced temperature jump are exponential for small jumps, indicative through two-state...