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Oleg Boyarkine

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Publications associées (73)

Initial Steps of Amyloidogenic Peptide Assembly Revealed by Cold-Ion Spectroscopy

Oleg Boyarkine, Natalia Nagornova, Vladimir Kopysov

The early stages of fibril formation are difficult to capture in solution. We use cold-ion spectroscopy to examine an 11-residue peptide derived from the protein transthyretin and clusters of this fibre-forming peptide containing up to five units in the ga ...

Wiley-Blackwell2018

Intrinsic structure of pentapeptide Leu-enkephalin: geometry optimization and validation by comparison of VSCF-PT2 calculations with cold ion spectroscopy

Oleg Boyarkine, Vladimir Kopysov, Aleksandr Pereverzev, Robert Benny Gerber

The intrinsic structure of an opioid peptide [Ala2, Leu5]-leucine enkephalin (ALE) has been investigated using first-principles based vibrational self-consistent field (VSCF) theory and cold ion spectroscopy. IR-UV double resonance spectroscopy revealed th ...

2018

Cold ion spectroscopy for structural identifications of biomolecules

Oleg Boyarkine

Over the last decade, the spectroscopy of cryogenically cold ions iso- lated in the gas phase has been developed as a new tool for structural elucidations of biological molecules. Cooling allows for vibrational resolution in UV and IR spectra of small to m ...

2018

Identification of Isomeric Ephedrines by Cold Ion UV Spectroscopy: Toward Practical Implementation

Oleg Boyarkine, Vladimir Kopysov

Ephedrine and pseudoephedrine are stimulant drugs whose use is prohibited in athletic competition by the World Anti Doping Agency (WADA) at very different threshold doping violation concentrations. We use a recently developed universal approach that integr ...

2017

A Decapeptide Hydrated by Two Waters: Conformers Determined by Theory and Validated by Cold Ion Spectroscopy

Oleg Boyarkine, Natalia Nagornova, Robert Benny Gerber

The intrinsic structures of biomolecules in the gas phase may not reflect their native solution geometries. Microsolvation of the molecules bridges the two environments, enabling a tracking of molecular structural changes upon hydration at the atomistic le ...

American Chemical Society2017

Exploring the relevance of gas-phase structures to biology: cold ion spectroscopy of the decapeptide neurokinin A

Oleg Boyarkine, Aleksandr Pereverzev

Linking the intrinsic tertiary structures of biomolecules to their native geometries is a central prerequisite for making gas-phase studies directly relevant to biology. The isolation of molecules in the gas phase eliminates hydrophilic interactions with s ...

Royal Society of Chemistry2017

High Susceptibility of Histidine to Charge Solvation Revealed by Cold Ion Spectroscopy

Oleg Boyarkine, Vladimir Kopysov, Aleksandr Pereverzev

Histidine remained the last aromatic amino acid for which the intrinsic spectroscopic properties and structures were obscure. We measured the UV and IR spectra of protonated histidine, isolated in the gas phase, using photofragmentation cold ion spectrosco ...

Wiley-Blackwell2017

Vibrational Signatures of Conformer-Specific Intramolecular Interactions in Protonated Tryptophan

Oleg Boyarkine, Natalia Nagornova, Aleksandr Pereverzev

Because of both experimental and computational challenges, protonated tryptophan has remained the last aromatic amino acid for which the intrinsic structures of low-energy conformers have not been unambiguously solved. The IR-IR UV hole-burning spectroscop ...

Amer Chemical Soc2016

Nonstatistical UV Fragmentation of Gas-Phase Peptides Reveals Conformers and Their Structural Features

Oleg Boyarkine, Vladimir Kopysov

Solving the 3D structure of a biomolecule requires recognition of its conformers and measurements of their individual structural identities, which can be compared with calculations. We employ the phenomenon of nonstatistical photofragmentation, detected by ...

Amer Chemical Soc2016

Resonance Energy Transfer Relates the Gas-Phase Structure and Pharmacological Activity of Opioid Peptides

Oleg Boyarkine, Vladimir Kopysov

Enkephalins are efficient pain-relief drugs that bind to transmembrane opioid receptors. One key structural param- eter that governs the pharmacological activity of these opioid peptides and is typically determined from condensed-phase structures is the di ...

Wiley-Blackwell2016

Method and apparatus for the analysis of molecules using mass spectrometry and optical spectroscopy

Oleg Boyarkine, Vladimir Kopysov

A method of analyzing molecules enabling chemical, structural and isomeric or conformational identification of the molecules, particularly in a stream from a chromatographic separation, comprising: generating ions from a sample of molecules to be analyzed; ...

2016

Colors for Molecular Masses: Fusion of Spectroscopy and Mass Spectrometry for Identification of Biomolecules

Oleg Boyarkine, Vladimir Kopysov

We present an approach that integrates ultraviolet (UV) photofragmentation spectroscopy of cold ions with high-resolution Orbitrap mass spectrometry (MS) and uses mathematical analysis of the recorded 2D data arrays for structural identification of biomole ...

Amer Chemical Soc2015

Dissociation threshold of H218O: Validating ab initio calculations by state-selective triple-resonance spectroscopy

Oleg Boyarkine

We employ state-selective triple-resonance vibrational overtone spectroscopy for a direct measurement of the lowest dissociation energy, Do, in the (H2O)-O-18 molecule. The measured value of 41 154.22 +/- 0.25 cm(-1) is in an excellent agreement with that, ...

Elsevier2015

Conformational Structures of a Decapeptide Validated by First Principles Calculations and Cold Ion Spectroscopy

Oleg Boyarkine, Thomas Rizzo, Natalia Nagornova, Vladimir Kopysov, Robert Benny Gerber

Calculated structures of the two most stable conformers of a protonated decapeptide gramicidin S in the gas phase have been validated by comparing the vibrational spectra, calculat- ed from first- principles and measured in a wide spectral range using infr ...

Wiley-V C H Verlag Gmbh2015

Cryogenic Methods for the Spectroscopy of Large, Biomolecular Ions

Oleg Boyarkine, Thomas Rizzo

Determining the conformation of biological molecules is key for understanding their function. The recent combination of mass spectrometry, cryogenic ion traps, and laser spectroscopy is providing new methods to interrogate individual conformations of pepti ...

Springer2015

Fragmentation mechanism of UV-excited peptides in the gas phase

Oleg Boyarkine, Thomas Rizzo, Aleksandra Zabuga, Michael Zachary Kamrath

We present evidence that following near-UV excitation, protonated tyrosine- or phenylalanine–containing peptides undergo intersystem crossing to produce a triplet species. This pathway competes with direct dissociation from the excited electronic state and ...

American Institute of Physics2014

Microhydration Effects on the Encapsulation of Potassium Ion by Dibenzo-18-Crown-6

Oleg Boyarkine, Thomas Rizzo, Yoshiya Inokuchi

We have measured electronic and conformer-specific vibrational spectra of hydrated dibenzo-18-crown-6 (DB18C6) complexes with potassium ion, K+center dot DB18C6 center dot(H2O)(n) (n = 1-5), in a cold, 22-pole ion trap. We also present for comparison spect ...

American Chemical Society2014

Accurate bond dissociation energy of water determined by triple-resonance vibrational spectroscopy and ab initio calculations

Oleg Boyarkine, Thomas Rizzo, Pavlo Maksyutenko, Oleg Aseev

Triple-resonance vibrational spectroscopy is used to determine the lowest dissociation energy, D0, for the water isotopologue HD16O as 41 239.7 ± 0.2 cm−1 and to improve D0 for H216O to 41 145.92 ± 0.12 cm−1. Ab initio calculations including systematic bas ...

Elsevier2013

Exploring the Mechanism of IR–UV Double-Resonance for Quantitative Spectroscopy of Protonated Polypeptides and Proteins

Oleg Boyarkine, Thomas Rizzo, Natalia Nagornova

Wiley-VCH Verlag GmbH2013

Laser Spectroscopic Study of Cold Host–Guest Complexes of Crown Ethers in the Gas Phase

Oleg Boyarkine, Thomas Rizzo, Yoshiya Inokuchi

A laser spectroscopic study on the structure and dynamics of cold host–guest inclusion complexes of crown ethers (CEs) with various neutral and ionic species in the gas phase is presented. The complexes with neutral guest species are formed by using supers ...

2013

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