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Oleg Boyarkine

Cette personne a quitté l’EPFL

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Publications associées (73)

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

Oleg Boyarkine, Natalia Nagornova

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

UV and IR spectroscopy of cold 1,2-dimethoxybenzene complexes with alkali metal ions

Thomas Rizzo, Oleg Boyarkine, Yoshiya Inokuchi

We report UV photodissociation (UVPD) and IR-UV double-resonance spectra of 1,2-dimethoxybenzene (DMB) complexes with alkali metal ions, M+•DMB (M = Li, Na, K, Rb, and Cs), in a cold 22-pole ion trap. The UVPD spectrum of the Li+ complex shows a strong ori ...

2012

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

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

Thomas Rizzo, Oleg Boyarkine, 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

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

Approaching the full set of energy levels of water

Thomas Rizzo, Oleg Boyarkine, Pavlo Maksyutenko

We report here measurements of rovibrational levels in the electronic ground state of water at the previously inaccessible energies above 26,000 cm-1. The use of laser double-resonance overtone excitation extends this limit to 34,200 cm-1, which correspond ...

2007

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

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

Fragmentation mechanism of UV-excited peptides in the gas phase

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

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

Oligomers of diphenylalanine examined using cold ion spectroscopy and neural network-based conformational search

Oleg Boyarkine, Vladimir Kopysov, Ruslan Yamaletdinov

Diphenylalanine (Phe2) is the primary building block of many self-assembling nanostructures that are important in biology and materials science. Understanding the detailed mechanism of their formation requires knowledge of the structural motives that the s ...

2024

Conformation-specific spectroscopy and photodissociation of cold, protonated tyrosine and phenylalanine

Thomas Rizzo, Oleg Boyarkine, Caroline Seaiby

We present here ultraviolet and infrared spectra of protonated aromatic amino acids in a cold, 22-pole ion trap. Ultraviolet photofragmentation spectra of protonated tyrosine and phenylalanine show vibronically resolved bands corresponding to different sta ...

2007

Spectroscopic studies of cold, gas-phase biomolecular ions

Thomas Rizzo, Oleg Boyarkine

While the marriage of mass spectrometry and laser spectroscopy is not new, developments over the last few years in this relationship have opened up new horizons for the spectroscopic study of biological molecules. The combination of electrospray ionization ...

2009

Microhydration of Biomolecules: Revealing the Native Structures by Cold Ion IR Spectroscopy

Oleg Boyarkine, Andrei Zviagin, Viktoriia Aladinskaia

The native-like structures of protonated glycine and peptide Gly3H+ were elucidated using cold ion IR spectroscopy of these biomolecules hydrated by a controlled number of water molecules. The complexes were generated directly from an aqueous solution usin ...

2021

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

Thomas Rizzo, Oleg Boyarkine, Natalia Nagornova

Wiley-VCH Verlag GmbH2013

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

State-resolved spectroscopy of high vibrational levels of water up to the dissociative continuum

Thomas Rizzo, Oleg Boyarkine, Maxim Grechko, Pavlo Maksyutenko

We summarize here our experimental studies of the high rovibrational energy levels of water. The use of double-resonance vibrational overtone excitation followed by energy-selective photofragmentation and laser-induced fluorescence detection of OH fragment ...

2012

Spectroscopy of Protonated Peptides Assisted by Infrared Multiple Photon Excitation

Thomas Rizzo, Oleg Boyarkine, Ulrich Lorenz, Georgios Papadopoulos

We report here a new technique for spectroscopic studies of protonated, gas- phase biomolecules and demonstrate its utility by measuring highly-resolved electronic and infrared spectra of peptides of up to 17 amino acids. After UV excitation of an aromatic ...

2009

Revealing the Structure of Tryptophan in Microhydrated Complexes by Cold Ion Spectroscopy

Oleg Boyarkine, Natalia Nagornova, Manuel Dömer, Andrei Zviagin, Ruslan Yamaletdinov

The geometry of biomolecules isolated in the gas phaseusuallydiffers substantially from their native structures in aqueous solution,which are the only ones truly relevant to life science. To connectthe high resolution of cold ion spectroscopy that can be a ...

2023

Electronic spectroscopy of cold, protonated tryptophan and tyrosine

Thomas Rizzo, Oleg Boyarkine, Anthi Kamariotou

We report here a new method to obtain electronic spectra of biomolecular ions that are produced in the gas phase by electrospray and cooled to ~10K in a 22-pole ion trap, and we demonstrate this technique by applying it to protonated tryptophan and tyrosin ...

2006

Conformational distribution of bradykinin [bk+2H]2+ revealed by cold ion spectroscopy coupled with FAIMS

Thomas Rizzo, Oleg Boyarkine, Georgios Papadopoulos, Annette Svendsen

We employ Cold Ion Spectroscopy (CIS) in conjunction with high-Field Asymmetric Waveform Ion Mobility Spectrometry (FAIMS) to study the peptide bradykinin in its doubly protonated charge state ([bk+2H]2+). Using FAIMS we partially separate the electrospray ...

Springer-Verlag2012

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

Oleg Boyarkine, Vladimir Kopysov, Natalia Nagornova

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