Publications de Valeriu Scutelnic

Structures of the (Imidazole)(n)H+ ... Ar (n=1,2,3) complexes determined from IR spectroscopy and quantum chemical calculations

Here, we present new cryogenic infrared spectra of the (Imidazole) H-n(+) (n=1,2,3) ions. The data was obtained using helium tagging infrared predissociation spectroscopy. The new results were compared with the data obtained by Gerardi et al. (Chem. Phys. ...

SPRINGER/PLENUM PUBLISHERS2023

Structural Insights from Tandem Mass Spectrometry, Ion Mobility-Mass Spectrometry, and Infrared/Ultraviolet Spectroscopy on Sphingonodin I: Lasso vs Branched-Cyclic Topoisomers

Thomas Rizzo, Valeriu Scutelnic

Lasso peptides form a class of ribosomally synthesized and post-translationally modified peptides (RiPPs) characterized by a mechanically interlocked topology, where the C-terminal tail of the peptide is threaded and trapped within an N-terminal macrolacta ...

AMER CHEMICAL SOC2021

Cryogenic Ion Spectroscopy for Identification of Monosaccharide Anomers

Thomas Rizzo, Valeriu Scutelnic

We combine conformer-selective, cryogenic infrared spectroscopy, quantum mechanical computations, and 18O substitution at the reducing end to determine the structural preferences of protonated glucosamine in the gas phase. Cryogenic infrared-infrared (IR-I ...

2019

Separation and Identification of Glycan Anomers Using Ultrahigh-Resolution Ion Mobility Spectrometry and Cryogenic Ion Spectroscopy

Thomas Rizzo, Ahmed Ben Faleh, Valeriu Scutelnic, Stephan Warnke

The analysis of carbohydrates, or glycans, is challenging for established structure-sensitive gas-phase methods. The multitude of possible stereo-, regio- and structural isomers make them substantially more complex to ana-lyze than DNA or proteins, and no ...

2019

High-throughput cryogenic spectroscopy for glycan analysis

Thomas Rizzo, Ahmed Ben Faleh, Valeriu Scutelnic, Stephan Warnke

A method for analyzing a plurality of molecules with cryogenic vibrational spectroscopy including the steps of providing a packet of molecules in a ionized form, injecting the packet into an ion mobility section, spatially separating the ions of the packet ...

2019

Can Mutational Analysis Be Used To Assist Structure Determination of Peptides?

Thomas Rizzo, Liudmila Voronina, Chiara Masellis, Valeriu Scutelnic

Mutational analysis is widely used to study the relationship between sequence and structure of proteins and peptides. It is often assumed that substituting a proline with another amino acid "locks" the peptide bond in the trans conformation, allowing only ...

2018

The Structure of the Protonated Serine Octamer

Thomas Rizzo, Ursula Röthlisberger, Aurelien Stephen Arnaud Gregor, Marta Andreia Da Silva Perez, Valeriu Scutelnic, Stephan Warnke, Carsten Baldauf

The amino acid serine has long been known to form a protonated “magic-number” cluster containing eight monomer units that shows an unusually high abundance in mass spectra and has a remarkable homochiral preference. Despite many experimental and theoretica ...

2018

Infrared Spectroscopy as a Probe of Electronic Energy Transfer

Thomas Rizzo, Aleksandra Zabuga, Antonio Prlj, Valeriu Scutelnic

We have combined electronic and vibrational spec- troscopy in a cryogenic ion trap to produce highly resolved, conformer-selective spectra for the ground and excited states of a peptide containing two chromophores. These spectra permit us to determine the ...

2018

Cryogenic infrared spectroscopy as a probe of structure and dynamics of biomolecules

Valeriu Scutelnic

The pivotal theory of molecular biology states that the structure of biomolecules is directly related to their function in living systems. In this way, the structural investigation of biological molecules allows understanding and intervening in the fundame ...

EPFL2018

Synthesis and Photophysical Characterization of Cyclometalated Ruthenium Complexes with N-Heterocyclic Carbene Ligands

Mohammad Khaja Nazeeruddin, Sadig Aghazada, Valeriu Scutelnic, Iwan Zimmermann

In the search of new ligand environment for the ruthenium(II) complexes with pyridine-type ligands, we developed seven new cyclometalated ruthenium complexes with N-heterocyclic carbenes (NHCs). In a two-step procedure, we synthesized complexes with the ge ...

American Chemical Society2017