62 research outputs found
Caught while Dissolving: Revealing the Interfacial Solvation of the Mg2+ Ions on the MgO Surface
Interfaces between water and materials are ubiquitous and are crucial in materials sciences and in biology, where investigating the interaction of water with the surface under ambient conditions is key to shedding light on the main processes occurring at the interface. Magnesium oxide is a popular model system to study the metal oxide-water interface, where, for sufficient water loadings, theoretical models have suggested that reconstructed surfaces involving hydrated Mg2+ metal ions may be energetically favored. In this work, by combining experimental and theoretical surface-selective ambient pressure X-ray absorption spectroscopy with multivariate curve resolution and molecular dynamics, we evidence in real time the occurrence of Mg2+ solvation at the interphase between MgO and solvating media such as water and methanol (MeOH). Further, we show that the Mg2+ surface ions undergo a reversible solvation process, we prove the dissolution/redeposition of the Mg2+ ions belonging to the MgO surface, and we demonstrate the formation of octahedral [Mg(H2O)6]2+ and [Mg(MeOH)6]2+ intermediate solvated species. The unique surface, electronic, and structural sensitivity of the developed technique may be beneficial to access often elusive properties of low-Z metal ion intermediates involved in interfacial processes of chemical and biological interest
On the applicability of the Tubulin-Based Polymorphism (TBP) genotyping method: a comprehensive guide illustrated through the application on different genetic resources in the legume family
Background
Plant discrimination is of relevance for taxonomic, evolutionary, breeding and nutritional studies. To this purpose, evidence is reported to demonstrate TBP (Tubulin-Based-Polymorphism) as a DNA-based method suitable for assessing plant diversity.
Results
Exploiting one of the most valuable features of TBP, that is the convenient and immediate application of the assay to groups of individuals that may belong to different taxa, we show that the TBP method can successfully discriminate different agricultural species and their crop wild relatives within the Papilionoideae subfamily. Detection of intraspecific variability is demonstrated by the genotyping of 27 different accessions of Phaseolus vulgaris.
Conclusions
These data illustrate TBP as a useful and versatile tool for plant genotyping. Since its potential has not yet been fully appreciated by the scientific community, we carefully report all the experimental details of a successful TBP protocol, while describing different applications, so that the method can be replicated in other laboratories
Catching the Reversible Formation and Reactivity of Surface Defective Sites in Metal-Organic Frameworks: An Operando Ambient Pressure-NEXAFS Investigation
In this work, we apply for the first time ambient pressure operando soft X-ray absorption spectroscopy (XAS) to investigate the location, structural properties, and reactivity of the defective sites present in the prototypical metal-organic framework HKUST-1. We obtained direct evidence that Cu+ defective sites form upon temperature treatment of the powdered form of HKUST-1 at 160 degrees C and that they are largely distributed on the material surface. Further, a thorough structural characterization of the Cu+/Cu2+ dimeric complexes arising from the temperature-induced dehydration/decarboxylation of the pristine Cu2+/Cu2+ paddlewheel units is reported. In addition to characterizing the surface defects, we demonstrate that CO2 may be reversibly adsorbed and desorbed from the surface defective Cu+/Cu2+ sites. These findings show that ambient pressure soft-XAS, combined with state-ofthe-art theoretical calculations, allowed us to shed light on the mechanism involving the decarboxylation of the paddlewheel units on the surface to yield Cu+/Cu2+ complexes and their reversible restoration upon exposure to gaseous CO2
Probing Structure and Reactivity of Metal Centers in Metal–Organic Frameworks by XAS Techniques
A XAFS study of the local environment and reactivity of Pt- sites in functionalized UiO-67 MOFs
The GENETPIG database: a tool for comparative mapping in pig (Sus scrofa)
The GENETPIG database has been established for storing and disseminating the results of the European project: ‘GENETPIG: identification of genes controlling economic traits in pig'. The partners of this project have mapped about 630 porcine and human ESTs onto the pig genome. The database collects the mapping results and links them to other sources of mapping data; this includes pig maps as well as available comparative mapping information. Functional annotation of the mapped ESTs is also given when a significant similarity to cognate genes was established. The database is accessible for consultation via the Internet at http://www.infobiogen.fr/services/Genetpi
Characterization of Maternal Antigen That Embryos Require (MATER/NLRP5) Gene and Protein in Pig Somatic Tissues and Germ Cells
Maternal effect genes produce mRNA or proteins that accumulate in the egg during oogenesis and control the developmental program until embryonic genome activation takes place. NLRP5 (NLR family, Pyrin domain containing 5), also called MATER (Maternal Antigen That Embryos Require) is one of the genes required for normal early embryonic development, although its precise function remains to be elucidated. The aim of the present study was to analyze the NLRP5 gene expression pattern and protein distribution in somatic tissues and germ cells in the pig. Reverse transcription was performed on mRNA from germinal vescicle (GV) oocytes and total RNA from spermatozoa and tissues from different organs. The transcript for NLRP5 gene was identified only in ovaries and oocytes. The presence of NLRP5 protein was detected only in ovaries by western blot analysis and immunohistochemistry
BRIEFINGS IN FUNCTIONAL GENOMICS AND PROTEOMICS. VOL 6. NO 4. 313^321
doi:10.1093/bfgp/elm036 Molecular approaches in pig breeding to improve meat qualit
Comparison of expression levels of fourteen genes involved in the lipid and energy metabolism in two pig breeds
Fat content, fatty acid composition and lean cut weight are important parameters which influence meat and carcass quality in pigs. Up to now, the genes involved in the regulation of the lipid and energy metabolism in porcine skeletal muscle and fat tissue are still relatively unknown. The aim of this study was to investigate the expression levels of fourteen genes (ACACA, ACLY, CES3, ENO3, FASN, INSIG2, LMNA, MTTP, ACVR1C, NAMPT, PLIN1, PLIN2, PLTP and SORT1) mapped on different chromosomes (1, 4, 7, 8, 9, 12, 15 and 17) which were chosen for their involvement in lipid or energy metabolism in porcine muscle and backfat tissue. Tissue samples from Italian Large White and Italian Duroc pig breeds were collected at the slaughterhouse and frozen in liquid nitrogen. After extraction, the mRNA was quantified by quantitative real time polymerase chain reaction (RT-PCR) and the transcription levels of the genes analysed were compared between breeds for each tissue. In the backfat tissue, differences were found for the ACACA, ACLY, and FASN genes whose highest gene expression levels were found in Italian Large White pigs. In addition, a correlation analysis was carried out between the transcription levels of the genes considered in each tissue and breed. Co-expression relationships still relatively unknown were identified, suggesting new associations between genes which in some cases differed between the two breeds. These results suggest differences between Italian Large White and Italian Duroc pig breeds determined at the genome level affecting carcass quality and fat traits
Tubulin-Based DNA Barcode: Principle and Applications to Complex Food Matrices
The DNA polymorphism diffusely present in the introns of the members of the Eukaryotic beta-tubulin gene families, can be conveniently used to establish a DNA barcoding method, named tubulin-based polymorphism (TBP), that can reliably assign specific genomic fingerprintings to any plant or/and animal species. Similarly, many plant varieties can also be barcoded by TBP. The method is based on a simple cell biology concept that finds a conveniently exploitable molecular basis. It does not depend on DNA sequencing as the most classically established DNA barcode strategies. Successful applications, diversified for the different target sequences or experimental purposes, have been reported in many different plant species and, of late, a new a version applicable to animal species, including fishes, has been developed. Also, the TBP method is currently used for the genetic authentication of plant material and derived food products. Due to the use of a couple of universal primer pairs, specific for plant and animal organisms, respectively, it is effective in metabarcoding a complex matrix allowing an easy and rapid recognition of the different species present in a mixture. A simple, dedicated database made up by the genomic profile of reference materials is also part of the analytical procedure. Here we will provide some example of the TBP application and will discuss its features and uses in comparison with the DNA sequencing-based methods
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