Category Archives: Our Publications

These are the scientific articles published by SeRMN personnel. Posts may contain a short description of the research work objective and relevance, in addition to the abstract of the article, the bibliographic reference, and the article DOI if available.

Saving time using different NMR concepts

Nolis, Pau, Kumar Motiram-Corral, Míriam Pérez-Trujillo & Teodor Parella. 2019. Broadband homodecoupled time-shared 1H-13C and 1H-15N HSQC experiments. Journal of Magnetic Resonance 298. 23–30. DOI: 10.1016/j.jmr.2018.11.00

The concepts of pure-shift NMR and time-shared NMR are merged in a single NMR experiment. A 13C/15N time-shared version of the real-time BIRD-based broadband homodecoupled HSQC experiment is described. This time-efficient approach affords simultaneously 1H-13C and 1H-15N pure-shift HSQC spectra in a single acquisition, while achieving substantial gains in both sensitivity and spectral resolution. We also present a related 13C/15N-F2-coupled homodecoupled version of the CLIP-HSQC experiment for the simultaneous measurement of 1JCH and 1JNH from the simplified doublets observed along the direct dimension. Finally, a novel J-resolved HSQC experiment has been designed for the simple and automated determination of both 1JCH/1JNH from a 2D J-resolved spectrum.

4 experiments in 1 shot

Motiram-Corral, Kumar, Míriam Pérez-Trujillo, Pau Nolis & Teodor Parella. 2018. Implementing one-shot multiple-FID acquisition into homonuclear and heteronuclear NMR experiments. Chemical Communications 54(96). 13507–13510. DOI: 10.1039/c8cc08065h

Multiple-FID acquisition (MFA) within the same scan is applied to acquire simultaneously multiple 2D spectra from a single NMR experiment. A discussion on the incorporation of the MFA strategy in several homonuclear and heteronuclear 2D pulse sequences is presented. As a proof of concept, a set of novel COSY, TOCSY and HMBC experiments are reported as a time-efficient solution in small-molecule NMR spectroscopy.

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MRI/MRS in treated Alzheimer mice

Montoliu-Gaya, Laia, Jofre Güell-Bosch, Gisela Esquerda-Canals, Alejandro R. Roda, Gabriel Serra-Mir, Silvia Lope-Piedrafita, José Luís Sánchez-Quesada & Sandra Villegas. 2018. Differential effects of apoE and apoJ mimetic peptides on the action of an anti-Aβ scFv in 3xTg-AD mice. Biochemical Pharmacology 155. 380–392. DOI: 10.1016/j.bcp.2018.07.012

Anti-Aβ immunotherapy has emerged as a promising approach to treat Alzheimer’s disease (AD). The single-chain variable fragment scFv-h3D6 is an anti-Aβ antibody fragment that lacks the Fc region, which is associated with the induction of microglial reactivity by the full-length monoclonal antibody bapineuzumab. ScFv-h3D6 was previously shown to restore the levels of apolipoprotein E (apoE) and apolipoprotein J (apoJ) in a tripletransgenic- AD (3xTg-AD) mouse model. Since apoE and apoJ play an important role in the development of AD, we aimed to study the in vivo effect of the combined therapy of scFv-h3D6 with apoE and apoJ mimetic peptides (MPs).

Continue reading MRI/MRS in treated Alzheimer mice

Exopolysaccharides from olive brines could reduce the adhesion of ETEC K88 to intestinal epithelial cells

Zhu, Yanan, Gemma González-Ortiz, Rufino Jiménez-Díaz, Míriam Pérez-Trujillo, Teodor Parella, Paola López-Colom & Susana María Martín-Orúe. 2018. Exopolysaccharides from olive brines could reduce the adhesion of ETEC K88 to intestinal epithelial cells. Food & Function 9(7). 3884–3894. DOI: https://doi.org/10.1039/c8fo00690c

This study aims to explore the biological functions of the isolated exopolysaccharides (EPSs) produced during the industrial fermentation of olives against enterotoxigenic E. coli (ETEC) K88. Exopolysaccharides were isolated from five industrial fermenters. Analysis of their monosaccharide composition by GLC revealed that the main components were glucose (27%–50%) and galactose (23%–33%) followed by rhamnose (4–23%) and arabinose (6–17%). The 1H NMR spectrum showed a very similar profile between samples, and a more in-depth analysis revealed the presence of an α-pyranose in the form of α-D-Glcp-(1→) and two different α-furanoses, with chemicals shift values, suggesting the presence of α-D-Glcf and α-D-Galf. Miniaturized in vitro tests demonstrated the ability of EPS samples to attach specifically to ETEC K88 (P < 0.05) with variable intensities. The competition test did not show the ability to block the ETEC K88 adhesion to IPEC-J2 cells; however, in the displacement test, all EPS samples were shown to effectively remove the pathogens attached to the cells (P < 0.01).

These results suggest that the EPSs produced during the fermentation of table green olives could interfere with the attachment of opportunistic pathogens onto the intestinal epithelial cells. This would open the possibility of novel functional properties for this traditional Mediterranean fermented food and for the isolated EPSs as candidates for nutraceutics to be used in human and/or animal diets in the prevention and treatment of ETEC diarrhoea.

Solid State NMR supports a new study on hydride composite for hydrogen storage

Bergemann, N., C. Pistidda, C. Milanese, M. Aramini, S. Huotari, P. Nolis, A. Santoru, M. R. Chierotti, A.-L. Chaudhary, M. D. Baro, T. Klassen & M. Dornheim. 2018. A hydride composite featuring mutual destabilisation and reversible boron exchange: Ca(BH4)2–Mg2NiH4. Journal of Materials Chemistry A 6(37). 17929–17946. DOI: 10.1039/c8ta04748k

The system Ca(BH4)2–Mg2NiH4 is used as a model to prove the unique possibility to fully reverse the borohydride decomposition process even in cases where the decomposition reaction leads to undesired stable boron containing species (boron sinks). The formation of MgNi2.5B2 directly from Ca(BH4)2 or from CaB12H12 and amorphous boron allows an unexpectedly easy transfer of the boron atoms to reversibly form Ca(BH4)2 during rehydrogenation. In addition, to the best of our knowledge, the mutual destabilisation of the starting reactants is observed for the first time in Ca(BH4)2 based Reactive Hydride Composite (RHC) systems. A detailed account of dehydrogenation and rehydrogenation reaction mechanisms as the function of applied experimental conditions is given.

PhD Thesis: Development of Resolution-Enhanced NMR Techniques for Improved Small Molecules Structural Analysis

Last July 14th 2018 Núria Marcó defended her PhD Thesis entitled: Development of Resolution-Enhanced NMR Techniques for Improved Small Molecules Structural Analysis

The present doctoral thesis is framed within the field of Nuclear Magnetic Resonance (NMR) spectroscopy.

NMR spectroscopy is an analytic technique and, therefore, one of its main objectives is to unravel the correct structure of the molecules analyzed.This present doctoral thesis  is focused on this main objective. This work consists in a compendium of 7 publications, written in several prestigious scientific journals, that develop in depth the efficient and accurate determination of the constitution, configuration and conformation of small molecules thanks to the application of resolution improvements techniques.

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Solid-State-NMR a useful tool for the characterization of Hydrogen Storage Composite System

Karimi, Fahim, María V.C. Riglos, Antonio Santoru, Armin Hoell, Vikram S. Raghuwanshi, Chiara Milanese, Nils Bergemann, Claudio Pistidda, Pau Nolis , Maria D. Baro, Gökhan Gizer, Thi-Thu Le, P. Klaus Pranzas, Martin Dornheim, Thomas Klassen, Andreas Schrey & Julián Puszkiel. 2018. In Situ Formation of TiB2 Nanoparticles for Enhanced Dehydrogenation / Hydrogenation Reaction Kinetics of LiBH4–MgH2 as a Reversible Solid-State Hydrogen Storage Composite System. The Journal of Physical Chemistry C 122(22). 11671–11681. DOI: 10.1021/acs.jpcc.8b02258

To enhance the dehydrogenation/rehydrogenation kinetic behavior of the LiBH4–MgH2 composite system, TiF4 is used as an additive. The effect of this additive on the hydride composite system has been studied by means of laboratory and advanced synchrotron techniques. Investigations on the synthesis and mechanism upon hydrogen interaction show that the addition of TiF4 to the LiBH4–MgH2 composite system during the milling procedure leads to the in situ formation of well-distributed nanosized TiB2 particles. These TiB2 nanoparticles act as nucleation agents for the formation of MgB2 upon dehydrogenation process of the hydride composite system. The effect of TiB2 nanoparticles is maintained upon cycling.  

NEW BOOK RELEASE: “Preclinical MRI methods and protocols”

García Martín, María Luisa & Pilar López Larrubia (eds.). 2018. Preclinical MRI. Methods in Molecular Biology series. Springer New York. DOI: 10.1007/978-1-4939-7531-0

This book was conceived with the idea of providing an update on a wide variety of preclinical MRI methods and protocols to help technicians and researchers interested in this technology. The basics of MRI physics are introduced, followed by chapters describing updated methodology and protocols for some standard and more advanced MRI techniques covering diffusion, perfusion, functional imaging, in-vivo spectroscopy (proton and heteronuclear), susceptibility contrast MRI… The book also contains some chapters where some applications of those methods are illustrated in animal models of several diseases including cancer, stroke and neurodegeneration. Protocols are described in a step-by-step approach, with interesting notes and tips at the end of each chapter, which -a priori- should allow the new worker to obtain successful results with the first attempt ;o) .

Simultaneous RCSA and RDC measurement

Marcó, Núria, Roberto R. Gil & Teodor Parella. 2018. Isotropic/Anisotropic NMR Editing by Resolution-Enhanced NMR Spectroscopy. ChemPhysChem 19(9). 1024–1029. DOI: 10.1002/cphc.201800094

Modern resolution-enhanced NMR techniques can monitor the in-situ discrimination of co-existing isotropic and anisotropic contributions of small molecules dissolved in weakly aligning PMMA/CDCl3 media. The simultaneous sign-sensitive determination of accurate Δδ(1H) and Δδ(13C) between isotropic and anisotropic signals,  and/or  1TCH and 1JCH coupling constants (and consequently 1H-13C RDCs and 1H/13C RCSAs) can be performed from spectral-aliased HSQC spectra.

Pulse Programs Code for Bruker:

Precise characterization of mycobacterial cell wall lipid PTTM

Molecule confirmation and structure characterization of pentatriacontatrienyl mycolate in Mycobacterium smegmatisby M. Llorens-Fons, E. Julián, M. Luquin and M. Pérez-Trujillo. Chemistry and Physics of Lipids, 2018, Accepted Manuscript. DOI: https://doi.org/10.1016/j.chemphyslip.2017.12.006

Mycobacterium smegmatis is often used to study the different components of mycobacterial cell wall. Mycolic acids are important components of mycobacterial cell wall that have been associated with virulence. Recently, a novel lipid containing mycolic acids has been described in M. smegmatis. However, some uncertainties regarding the structure of this molecule named mycolate ester wax have been reported. The objective of this work was to perform an in depth structural study of this molecule for its precise characterization. Using 1H and 13C NMR spectroscopy, the molecular structure of mycolate ester wax found in M. smegmatis has been elucidated. The characterization was complemented with MS analyses. This molecule is formed by a carbon chain with three methyl substituted olefinic units and a mycolate structure with trans double bonds and cis cyclopropane rings. The present molecular study will facilitate the detection and identification of pentatriacontatrienyl mycolate (PTTM) in future studies by the performance of a simple 1D 1H NMR experiment.