Publications by authors named "J Sebestik"

Chiral 2-halopropionic acids and their derivatives were synthesized and their properties studied computationally using Raman and Raman optical activity (ROA) spectroscopy. For neat acids present as liquids small amount of water led to significant changes in the spectra, resulting even to flipping of some ROA band signs. We find this interesting for the role water plays in interpretation of vibrational optical activity spectra of biomolecules.

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A collaborative, open-science team undertook discovery of novel small molecule inhibitors of the SARS-CoV-2 nsp16-nsp10 2'--methyltransferase using a high throughput screening approach with the potential to reveal new inhibition strategies. This screen yielded compound , a ligand possessing an electron-deficient double bond, as an inhibitor of SARS-CoV-2 nsp16 activity. Surprisingly, X-ray crystal structures revealed that covalently binds within a previously unrecognized cryptic pocket near the -adenosylmethionine binding cleft in a manner that prevents occupation by -adenosylmethionine.

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Resonance Raman optical activity (RROA) spectra with high sensitivity reveal details on molecular structure, chirality, and excited electronic properties. Despite the difficulty of the measurements, the recorded data for the Co(III) complex with S,S-N,N-ethylenediaminedisuccinic acid are of exceptional quality and, coupled with the theory, spectacularly document the molecular behavior in resonance. This includes a huge enhancement of the chiral scattering, contribution of the antisymmetric polarizabilities to the signal, and the Herzberg-Teller effect significantly shaping the spectra.

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Arsenic of natural or industrial origin often occurs in water and makes it impotable. Due to its high toxicity, very sensitive detection is required. In the present study an ultra-sensitive arsenite (As) sensing is reported, based on aggregation-aided surface-enhanced Raman scattering (AA-SERS) of modified silver colloids.

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Oxidative stress may cause extended tyrosine posttranslational modifications of peptides and proteins. The 3-nitro-L-tyrosine (Nit), which is typically formed, affects protein behavior during neurodegenerative processes, such as Alzheimer's and Parkinson's diseases. Such metabolic products may be conveniently detected at very low concentrations by surface enhanced Raman spectroscopy (SERS).

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