All posts by Miriam

Tuberculosis mycobacterium and microscopic cords formation. Related to their virulence

“Cyclopropanation of α-mycolic acids is not required for cording in non-tuberculous mycobacteria” Cecilia Brambilla, Alejandro Sánchez-Chardi, Míriam Pérez-Trujillo, Esther Julián, Marina Luquin.  Microbiology, March 2012. DOI: 10.1099/mic.0.057919-0

Mycobacterium tuberculosis and Mycobacterium bovis are the principal agents responsible for human tuberculosis and tuberculosis in domestic and wild animals. Both form microscopic cords, a phenotypic characteristic that has been related to their virulence. The compounds responsible for cording are unknown, but a recent work has shown that cording could be related to the fine structure of α-mycolic acids. Continue reading Tuberculosis mycobacterium and microscopic cords formation. Related to their virulence

Metabolic profiling for the detection of early effects of environmental and lifestyle exposure to cadmium.

“Metabolic Profiling Detects Early Effects of Environmental and Lifestyle Exposure to Cadmium in a Human Population” JK Ellis, TJ Athersuch, LDK Thomas, F Teichert, M Pérez-Trujillo, C Svendsen, D J. Spurgeon, R Singh, L Järup, JG Bundy and HC Keun.  BMC Medicine, February 2012.  DOI: 10.1186/1741-7015-10-61

The ‘exposome’ represents the accumulation of all environmental exposures across a lifetime. Top-down strategies are required to assess something this comprehensive, and could transform our understanding of how environmental factors affect human health. Metabolic profiling (metabonomics / metabolomics)  defines an individual’s metabolic phenotype, which is influenced by genotype, diet, lifestyle, health and xenobiotic exposure, and could also reveal intermediate biomarkers for disease risk that reflect adaptive response to exposure. Continue reading Metabolic profiling for the detection of early effects of environmental and lifestyle exposure to cadmium.

Presentations to the Ibero-American NMR & GERMN Bienal & Iberian NMR joint meeting

Next week several SeRMN members will present our research work at the IV Ibero-American NMR – VI GERMN Bienal – III Iberian NMR joint meeting that will take place in Aveiro (Portugal) from 25th to 28th September. Find below a summary of our contributions.

Continue reading Presentations to the Ibero-American NMR & GERMN Bienal & Iberian NMR joint meeting

ECOMETABOLOMICS: Metabolomics in Ecological Studies

“Strong relationship between elemental stoichiometry and metabolome in plants” Albert Rivas-Ubach, Jordi Sardans, Miriam Pérez-Trujillo, Marc Estiarte and Josep Peñuelas.  PNAS, February 2012. DOI: 10.1073/pnas.1116092109

Shifts in the elemental stoichiometry of organisms in response to their ontogeny and to changing environmental conditions should be related to metabolomic changes because elements operate mostly as parts of molecular compounds. Here we show this relationship in leaves of Erica multiflora throughout their seasonal development and in response to moderate experimental field conditions of drought and warming. Continue reading ECOMETABOLOMICS: Metabolomics in Ecological Studies

HPLC-DAD-(SPE)-NMR/MS II: fundamentals and working modes

This hyphenated technique combines HPLC with three complementary detection techniques – NMR Spectroscopy, Mass Spectrometry and Diode Array Detection. It is a highly rich information source, which can be obtained by one-shot analysis.

There are three different modes of work: Flow-NMR, Stop-Flow and SPE-storage; and depending on the scientific problem one or another will be the most adequate. Continue reading HPLC-DAD-(SPE)-NMR/MS II: fundamentals and working modes

CHIRAL METABONOMICS: Giving Metabonomics a Chiral Dimension

“Chiral Metabonomics: 1H NMR-Based Enantiospecific Differentiation of Metabolites in Human Urine via Direct Cosolvation with β-Cyclodextrin” Míriam Pérez-Trujillo, John C. Lindon, Teodor Parella, Hector C. Keun, Jeremy K. Nicholson and Toby J. Athersuch. Analytical Chemistry, February 2012 DOI:10.1021/ac203291d

Differences in molecular chirality remain an important issue in drug metabolism and pharmacokinetics for the pharmaceutical industry and regulatory authorities and chirality is an important feature of many endogenous metabolites. We present a 1H NMR-based method for the rapid, direct differentiation and identification of chiral drug enantiomers in human urine without pre-treatment of any kind. Continue reading CHIRAL METABONOMICS: Giving Metabonomics a Chiral Dimension

HPLC-DAD-(SPE)-NMR/MS I: all in one technique for the analysis of mixtures

The combination of liquid chromatography with three complementary detection techniques – NMR Spectroscopy, Mass Spectrometry and Diode Array Detection, provides highly rich information in a one-shot analysis.

The possibility of a post-chromatography storage /concentration of the chromatographic peaks of interest, using a SPE (Solid Phase Extraction) system, together with the use of cool probes,  increases the sensitivity of the NMR detection.

Continue reading HPLC-DAD-(SPE)-NMR/MS I: all in one technique for the analysis of mixtures

Revisited mycolic acid pattern of Mycobacterium confluentis using thin-layer chromatography

“Revisited mycolic acid pattern of Mycobacterium confluentis using thin-layer chromatography”, by Silvia Secanella-Fandos, Marina Luquin, Míriam Pérez-Trujillo, Esther Julián; Journal of Chromatography B, Article in Press (2011). doi:10.1016/j.jchromb.2011.08.001

The profile of mycolic acids from Mycobacterium confluentis has not been adequately published. However, the definition of the composition of mycolic acids is a critical element for describing new mycobacterial species. Thus, an erroneously published profile can lead to confusing citations. Continue reading Revisited mycolic acid pattern of Mycobacterium confluentis using thin-layer chromatography

Conference: Metabolomics

Dr Toby Athersuch will be giving a talk on May the 20th at 12:00 h in the Sala de Graus 2, Facultat de Ciències i Biociències, Campus UAB. His talk is entitled Adventures in metabolic hyperspace: an overview of metabonomic approaches and applications. (Conference announcement: Conferència Toby – SeRMN)

Toby AthersuchDr Toby Athersuch is a Lecturer in Environmental Toxicology & Biomarkers in the MRC-HPA Centre for Environment & Health (Imperial College London). His appointment is jointly held between Biomolecular Medicine in the Department of Surgery & Cancer, and The Department of Epidemiology & Biostatistics in the School of Public Health. His research is primarily focused on the development and application of state-of-the-art analytical techniques such as high-resolution nuclear magnetic resonance (NMR) spectroscopic and mass spectrometric (MS) methods to the study of molecular mechanisms of human disease processes.  The application of metabolic profiling and other integrated post-genomic profiling technologies to answering epidemiological questions using various study designs is a rapidly expanding field of research, and requires the development of profiling techniques to underpin the required individual-level analyses. (See more: Short Bio – Toby Athersuch )

All interested individuals are welcome to attend this session.

Identification of compounds of biological significance in foodstuffs by LC-NMR/MS. Olive oil

There is a great interest in understanding the biochemical basis for the reported beneficial health effects of particular diets or food groups. Characterising the wide variety of nutrients in the things we eat and drink in detail is a substantial analytical challenge, especially when numerous sets of molecules in such mixtures may have very similar chemical structures.

Continue reading Identification of compounds of biological significance in foodstuffs by LC-NMR/MS. Olive oil