Abstract α-Synuclein is an intrinsically disordered protein that can self-aggregate and plays a major role in Parkinson’s disease (PD). Elevated levels of certain metal ions are found aggregates neurons people suffering from PD, environmental exposure has also been linked with neurodegeneration. Importantly, cellular interactions ions, particularly Ca 2+ , have recently reported as key for α-synuclein’s physiological function at the pre-synapse. Here we study effects ion interaction...

Abstract The ability to synthesise lemniscular molecules allow for the study and application of their chiroptical properties is a notable technical challenge. Herein, we report design synthesis enantiomers [5]helicenoid derived molecular lemniscate, in which two homochiral helicenes are linked via formation azine motifs. We demonstrate that these molecules, helicenoid constituents, also excellent chiral dopants induce dissymmetry ground excited states achiral emissive polymer F8BT, leading...

High-resolution resonance Raman (RR) and optical activity (ROA) spectra of cytochrome c were obtained in order to perform full assignment spectral features the ROA spectrum. The spectrum revealed a distinct signature pattern due enhanced skeletal porphyrin vibrations, more pronounced than any contribution from protein backbone. Combining intrinsic properties with surface plasmon enhancement achieved colloidal silver particles, scattering (SERRS) (SERROA) successfully at concentrations as low...

The effect of protonation on amino acid monomers and protein phosphorylation was studied by means a combination Raman scattering optical activity (ROA). In the past, identifying spectral variations in phosphorylated proteins arising from either phosphate stretch or amide vibrational modes has proven to be challenging mainly due loss P═O band intensity presence phosphate. By contrast, we have developed novel strategy based careful monitoring sample pH thereby modified state, such that these...

In the past few decades, Raman optical activity (ROA) spectroscopy has been shown to be very sensitive solution structure of peptides and proteins. A major urgent challenge remains need make detailed assignments experimental ROA patterns relate those adopted by protein. years, theoretical developments implementations theory have made it possible use quantum chemical methods compute spectra peptides. this work, a large database peptide model structures describing allowed backbone...

Many current anti-cancer therapies rely on increasing the intracellular reactive oxygen and nitrogen species (RONS) contents with aim to induce irreparable damage, which subsequently results in tumor cell death. A novel tool cancer therapy is use of cold atmospheric plasma (CAP), has been found be very effective treatment many different types vitro as well vivo, mainly through vast generation RONS. One key determinants cell's fate will interaction RONS, generated by CAP, important proteins,...

The Raman optical activity (ROA) spectra of both enantiomers 2-Br-hexahelicene in chloroform solution have been measured the range 1700–300 cm–1. Density functional theory (DFT) calculations accurately reproduce observed features. most intense ROA features are also features, region 1350–1400 cm–1, and correspond to so-called D-modes, which play a major role coronene other PAHs (polycyclic aromatic hydrocarbons). Together with detailed analysis normal mode structure, polarizability tensors...

Raman optical activity combined with state-of-the-art computational approaches successfully probes the conformational space of two important carbohydrates.

Alpha‐synuclein ( α ‐syn) is a 140 residue protein that plays central role in Parkinson's disease and other neurological disorders. The precise function pathological properties of ‐syn remain however poorly understood. While considered to be flexible disordered under native conditions, its ability adopt variety conformational ensembles depending on the environment related pathology. Raman optical activity (ROA) chiroptical spectroscopic technique uniquely sensitive secondary structure...

Sugars are crucial components in biosystems and industrial applications. In aqueous environments, the natural state of short saccharides or charged glycosaminoglycans is floating wiggling solution. Therefore, tools to characterize their structure a native environment but not always available. Here, we show that combination Raman/ROA and, on occasions, NMR experiments with Molecular Dynamics (MD) Quantum Mechanics (QM) viable method gain insights into structural features sugars solutions....

Vibrational absorption (VA) and vibrational circular dichroism (VCD) spectroscopy was applied in the analysis of low lying electronic transitions a triplet ground state cobalt(III) coordination compound. The spectroscopic measurements were performed on tetrabutylammonium salt (6S,7S)-1,3,5,8,10,12-hexaaza-2,4,9,11-tetraoxo-6,7-diphenyl-dodecanato(4-)cobaltate(III) DMSO solution potassium bromide pellets. chiral anion exhibits an unusual geometry for cobalt(III), being four-coordinate,...

Using surface enhanced ROA (SEROA), novel results are achieved by combining Raman optical activity (ROA) and resonance scattering (SERRS), applied on myoglobin. The novelty of this work is in reporting for the first time chiral a study performed protein at single molecule level. This work, using silver nanoparticles laser excitation 532 nm, only became feasible when concentrations nanoparticles, aggregation agent NaCl studied were optimized series systematic optimization steps. spectral...

A revealing signature: The glycan structure of intact yeast external invertase, a high-mannose glycoprotein used as biocatalyst, was investigated by using Raman optical activity (ROA) spectroscopy. conformational preferences present in mannose-containing di- and trisaccharides were found to be preserved the chains, with secondary polpeptide backbone suppressed.

Abstract The mechanical properties of agarose‐derived hydrogels depend on the scaffolding polysaccharide network. To identify and quantify such higher order structure, we applied Raman optical activity (ROA)—a spectroscopic technique that is highly sensitive toward carbohydrates—on native agarose chemically modified in gel phase for first time. By spectral global fitting, isolated features change as a function backbone carboxylation (28, 40, 50, 60, 80, 93 %) from other remain unchanged. We...

By further refining our DFT/MM protocol that allows for the crucial influence of hydration, we show it is possible to achieve near-perfect agreement between observed and calculated ROA spectra.

Artemisinin and two of its derivatives, dihydroartemisinin artesunate, front line drugs against malaria, were studied using Raman optical activity (ROA), vibrational circular dichroism (VCD) experiments density functional theory (DFT) calculations.

Abstract The samples used for the first observations of vibrational Raman optical activity (ROA) in 1972, namely both enantiomers 1‐phenylethanol and 1‐phenylethylamine, have been revisited using a modern commercial ROA instrument together with state‐of‐the‐art ab initio calculations. simulated spectra reveal time origins reported signals, which comprised similar couplets alcohol amine spectral range ∼280–400 cm −1 . results demonstrate how easy routine measurements become, current...

Splitting it up: Excellent agreement between the experimental and quantum-chemically simulated Raman optical activity (ROA) spectrum of (+)-poly(trityl methacrylate) shows that polymer backbone adopts a left-handed helical conformation while trityl side groups display propeller conformation. Thus ROA can be used to determine complete structure synthetic chiral polymers in solution.

Upon dissolving in dimethyl sulfoxide (DMSO), native insulin and amyloid fibrils convert into an identical disordered structural state based on IR spectral characteristics. Here, we investigate the DMSO-denatured of using a number spectroscopic methods: near-UV circular dichroism, infrared absorption spectroscopy, vibrational dichroism (VCD), Raman scattering, optical activity (ROA), as well by carrying out 140-ns-long molecular dynamics (MD) simulations DMSO-dissolved monomers. According to...

Raman optical activity reflects differences in the secondary structure of chondroitin caused by its sulfation.

Raman and specifically optical activity (ROA) spectroscopy are very sensitive to the solution structure conformation of biomolecules. Because this strong conformational sensitivity, density functional theory (DFT) calculations often used get a better understanding experimentally observed spectral patterns. While e.g. for carbohydrate water molecules that surround solute have been demonstrated be vital importance accurate modelled ROA spectra, effect explicit on calculated patterns peptides...

Synthesis of an array differentially sulfated GlcN-IdoA disaccharides, accessible on good scale, directly from l-iduronate components is described. These are specifically directed to provide the sulfation variability at key most common biologically relevant sulfation-variable l-IdoA O-2 and d-GlcN O-6 amino sites this heparin disaccharide. This sulfation-varied matrix has allowed first evaluation using Raman/ROA spectroscopy characterize changes in spectra as a function both site level with...