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Publications associées (27)

cgNA+: A sequence-dependent coarse-grain model of double-stranded nucleic acids

Rahul Sharma

DNA mechanics plays a crucial role in many biological processes, including nucleosome positioning and protein-DNA interactions. It is believed that nature employs epigenetic modifications in DNA to further regulate gene expression. Moreover, double-strande ...

EPFL2023

Visualizing Chiral Interactions in Carbohydrates Adsorbed on Au(111) by High-Resolution STM Imaging

Klaus Kern, Stephan Rauschenbach, Uta Schlickum

Carbohydrates are the most abundant organic material on Earth and the structural "material of choice" in many living systems. Nevertheless, design and engineering of synthetic carbohydrate materials presently lag behind that for protein and nucleic acids. ...

Wiley-VCH Verlag GmbH2023

Identification of Mobility-Resolved N-Glycan Isomers

Thomas Rizzo, Ahmed Ben Faleh, Stephan Warnke, Priyanka Bansal, Robert Paul Pellegrinelli

Glycan analysis has evolved considerably during the last decade. The advent of high-resolution ion-mobility spectrometry has enabled the separation of isomers with only the slightest of structural differences. However, the ability to separate such species ...

AMER CHEMICAL SOC2022

A New Strategy Coupling Ion-Mobility-Selective CID and Cryogenic IR Spectroscopy to Identify Glycan Anomers

Thomas Rizzo, Ahmed Ben Faleh, Stephan Warnke, Eduardo Carrascosa Casado, Priyanka Bansal, Robert Paul Pellegrinelli, Lei Yue

Determining the primary structure of glycans remains challenging due to their isomeric complexity. While high-resolution ion mobility spectrometry (IMS) has recently allowed distinguishing between many glycan isomers, the arrival-time distributions (ATDs) ...

2022

Combining multi-stage ion mobility spectrometry with cryogenic infrared spectroscopy for glycan analysis

Priyanka Bansal

Structural analysis of biomolecules is essential to understanding biological processes. Among the various classes of biomolecules, glycans have gained significant attention recently due to their ubiquitous roles in biological systems. However, study of gly ...

EPFL2022

Identifying Mixtures of Isomeric Human Milk Oligosaccharides by the Decomposition of IR Spectral Fingerprints

Thomas Rizzo, Ahmed Ben Faleh, Stephan Warnke, Vasyl Yatsyna, Ali H Abikhodr

The analysis of glycans presents a significant challenge that arises from their isomeric heterogeneity. While high-resolution ion mobility spectrometry (IMS) has shown the ability to resolve subtly different glycan isomers, their unambiguous assignment rem ...

2021

Combining cryognic ion spectroscopy with ion mobility for the study of glycan fragmentation

Robert Paul Pellegrinelli

The importance of glycans in biological processes are matched by their structural complexity. Coating the surface of most living cells, glycans play key roles in many biological processes, and the role they play is closely related to their structures. Stru ...

EPFL2021

Equilibrium and non-equilibrium furanose selection in the ribose isomerisation network

Paolo De Los Rios, Francesco Piazza, Daniel Maria Busiello, Shiling Liang

The exclusive presence of beta -D-ribofuranose in nucleic acids is still a conundrum in prebiotic chemistry, given that pyranose species are substantially more stable at equilibrium. However, a precise characterisation of the relative furanose/pyranose fra ...

Nature Research2021

Advanced characterization of regioselectively substituted methylcellulose model compounds by DNP enhanced solid-state NMR spectroscopy

David Lyndon Emsley, Pierrick Berruyer, Pinelopi Moutzouri

Dynamic Nuclear Polarization MAS NMR is introduced to characterize model methylcellulose ether compounds at natural isotopic abundance. In particular an approach is provided to determine the position of the methyl ether group within the repeating unit. Spe ...

2021

Structural and analytical identifications of biomolecules by cold ion spectroscopy of non-covalent complexes

Erik Saparbayev

Non-covalent interactions are ubiquitous in nature. The diversity and functionality of these interactions are employed by nature as a universal tool for building the molecular mechanism of life. Although weak, these interactions play a key role in both for ...

EPFL2021

Stabilization strategies in biomass depolymerization using chemical functionalization

Jeremy Luterbacher, Ydna Marie Questell-Santiago

A central feature of most lignocellulosic-biomass-valorization strategies is the depolymerization of all its three major constituents: cellulose and hemicellulose to simple sugars, and lignin to phenolic monomers. However, reactive intermediates, generally ...

2020

Revealing Single-Bond Anomeric Selectivity in Carbohydrate-Protein Interactions

Oleg Boyarkine, Aleksandr Pereverzev, Ruslan Yamaletdinov, Viktoriia Aladinskaia

The noncovalent binding of proteins to glycans is amazingly selective to the isoforms of carbohydrates, including alpha/beta anomers that coexist in solution. We isolate in the gas phase and study at the atomic level the simplest model system: noncovalent ...

AMER CHEMICAL SOC2020

Intermolecular Palladium(0)-Catalyzed Atropo-enantioselective C-H Arylation of Heteroarenes

Nicolai Cramer, Qui-Hien Nguyen

Atropisomeric (hetero)biaryls are motifs with increasing significance in ligands, natural products, and biologically active molecules. The straightforward construction of the stereogenic axis by efficient C-H functionalization methods is extremely rare and ...

2020

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

Interplay of H-Bonds with Aromatics in Isolated Complexes Identifies Isomeric Carbohydrates

Oleg Boyarkine, Vladimir Kopysov, Aleksandr Pereverzev, Ruslan Yamaletdinov

The tremendous isomeric diversity of carbohydrates enables a wide range of their biological functions but makes the identification and study of these molecules difficult. We investigated the ability of intermolecular interactions to communicate structural ...

Wiley-VCH Verlag GmbH2019

Generation of Heteroatom Stereocenters by Enantioselective C-H Functionalization

Nicolai Cramer, Johannes Diesel

C-H functionalization has been established as an efficient way to generate molecular complexity. The formation of stereogenic carbon atoms by asymmetric C-H functionalization has seen tremendous progress over the past decade. More recently, the direct cata ...

2019

Bioconversion of pentose sugars to value added chemicals and fuels: Recent trends, challenges and possibilities

Edgard Gnansounou

Most of the crop plants contain about 30% of hemicelluloses comprising D-xylose and D-arabinose. One of the major limitation for the use of pentose sugars is that high purity grade D-xylose and D-arabinose are yet to be produced as commodity chemicals. Res ...

Elsevier2018

Cryogenic Vibrational Spectroscopy Provides Unique Fingerprints for Glycan Identification

Thomas Rizzo, Michael Zachary Kamrath, Chiara Masellis

The structural characterization of glycans by mass spectrometry is particularly challenging. This is because of the high degree of isomerism in which glycans of the same mass can differ in their stereochemistry, attachment points, and degree of branching. ...

2017

Molecular Imaging of Biopolymers Enabled by Electrospray-Ion Beam Deposition

Sabine Abb

Biomolecular functional complexes often serve as inspiration for the development of artificial molecular nanostructures. The functionality of the biomolecular structures is based on complex and adaptable binding motifs that have evolved over billions of ye ...

EPFL2017

Glycosaminoglycan Analysis by Cryogenic Messenger-Tagging IR Spectroscopy Combined with IMS-MS

Thomas Rizzo, Michael Zachary Kamrath, Chiara Masellis

We combine ion mobility spectrometry with cryogenic, messenger-tagging, infrared spectroscopy and mass spectrometry to . identify different isomeric disaccharides of chondroitin sulfate (CS) and heparan sulfate (HS), which are representatives of two major ...

2017