Search results for "maldi-tof"
showing 10 items of 39 documents
Effects of the LPA1 Receptor Deficiency and Stress on the Hippocampal LPA Species in Mice
2019
Lysophosphatidic acid (LPA) is an important bioactive lipid species that functions in intracellular signaling through six characterized G protein-coupled receptors (LPA1-6). Among these receptors, LPA1 is a strong candidate to mediate the central effects of LPA on emotion and may be involved in promoting normal emotional behaviors. Alterations in this receptor may induce vulnerability to stress and predispose an individual to a psychopathological disease. In fact, mice lacking the LPA1 receptor exhibit emotional dysregulation and cognitive alterations in hippocampus-dependent tasks. Moreover, the loss of this receptor results in a phenotype of low resilience with dysfunctional coping in res…
Shell palaeoproteomics: first application of peptide mass fingerprinting for the rapid identification of mollusc shells in archaeology.
2020
10 pages; International audience; Molluscs were one of the most widely-used natural resources in the past, and their shells are abundant among archaeological findings. However, our knowledge of the variety of shells that were circulating in prehistoric times (and thus their socio-economic and cultural value) is scarce due to the difficulty of achieving taxonomic determination of fragmented and/or worked remains. This study aims to obtain molecular barcodes based on peptide mass fingerprints (PMFs) of intracrystalline proteins, in order to obtain shell identification. Palaeoproteomic applications on shells are challenging, due to low concentration of molluscan proteins and an incomplete unde…
The Complete Structure of the Core Oligosaccharide from Edwardsiella tarda EIB 202 Lipopolysaccharide
2017
The chemical structure and genomics of the lipopolysaccharide (LPS) core oligosaccharide of pathogenic Edwardsiella tarda strain EIB 202 were studied for the first time. The complete gene assignment for all LPS core biosynthesis gene functions was acquired. The complete structure of core oligosaccharide was investigated by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy, electrospray ionization mass spectrometry MSn, and matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry. The following structure of the undecasaccharide was established: The heterogeneous appearance of the core oligosaccharide structure was due to the partial lack of β-d-Galp and the replace…
Development of a database for the rapid and accurate routine identification of Achromobacter species by matrix-assisted laser desorption/ionization-t…
2019
International audience; Objectives: Achromobacter spp. are emerging pathogens in respiratory samples from cystic fibrosis patients. The current reference methods (nrdA-sequencing or multilocus sequence typing) can identify 18 species which are often misidentified by conventional techniques as A. xylosoxidans. A few studies have suggested that matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF/MS) provides accurate identification of the genus but not of species. The aims of this study were (a) to generate a database for MALDI-TOF/MS Bruker including the 18 species, (b) to evaluate the suitability of the database for routine laboratory identification, and …
Can MALDI-TOF Mass Spectrometry Reasonably Type Bacteria?
2017
International audience; Bacterial typing is crucial to tackle the spread of bacterial pathogens but current methods are time-consuming and costly. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has been recently integrated into the microbiology laboratory workflow for a quick and low-cost microbial species identification. Independent research groups have successfully redirected the original function of this technology from their primary purpose to discriminate subgroups within pathogen species. However, identical bacterial subgroups could be identified by unrelated peaks by independent methods, thus limiting their robustness and exportability. We…
The O-antigen of Plesiomonas shigelloides serotype O36 containing pseudaminic acid
2016
The structure of the repeating unit of O-antigen of Plesiomonas shigelloides serotype O36 has been investigated by 1H and 13C NMR spectroscopy, matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry and chemical methods. The new structure of trisaccharide has been established: →4)-β-Pse5Ac7(R3Hb)-(2 → 4)-β-D-Galp-(1 → 3)-β-D-GlcpNAc-(1→ These trisaccharide O-antigen units substitute the core undecasaccharide at C-4 of the β-D-GlcpNAc residue. The core oligosaccharide and lipid A are identical with these of the serotype O17 (PCM 2231) (Maciejewska, A., Lukasiewicz, J., Kaszowska, M., Jachymek, W., Man-Kupisinska, A.; Lugowski, C. Mar. Drugs.2013, 11 (2), 440–454; Lukasi…
Variance component analysis to assess protein quantification in biomarker discovery. Application to MALDI-TOF mass spectrometry.
2017
International audience; Controlling the technological variability on an analytical chain is critical for biomarker discovery. The sources of technological variability should be modeled, which calls for specific experimental design, signal processing, and statistical analysis. Furthermore, with unbalanced data, the various components of variability cannot be estimated with the sequential or adjusted sums of squares of usual software programs. We propose a novel approach to variance component analysis with application to the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) technology and use this approach for protein quantification by a classical signal processing algori…
Autentificación de cepas de la CECT mediante MALDI-TOF MS y GC FAME
2013
Las colecciones de cultivo microbianas son organizaciones, generalmente oficiales, cuya principal misión es conservar a largo plazo cepas de microorganismos, y suministrarlas, previa petición, a laboratorios, empresas y centros que requieran microorganismos para investigación, controles de calidad, docencia o para numerosas aplicaciones biotecnológicas. Además, las colecciones de cultivo, para ser consideradas como tal, deben cumplir ciertas normas relacionadas con la recolección, la autentificación, el mantenimiento y la distribución de los cultivos de microorganismos, así como la catalogación y los sistemas de información Una de las tareas más importantes en una colección pública es que e…
Baktērijas Borrelia burgdorferi proteīna BBP28 strukturālie pētījumi
2017
Laima slimība ir visizplatītākā ar vektoriem pārnēsātā slimība Amerikas Savienotajās Valstīs. Neraugoties uz tās plašo izplatību un smagajiem slimības simptomiem, pret to vēl aizvien nav pieejama vakcīna. Darba mērķis bija ekspresēt Laima slimības izraisītājas, baktērijas (Borrelia burgdorferi), ar membrānu saistīto lipoproteīnu BBP28 un noteikt tā struktūru. Izmantojot KMR datus, tika aprēķinātas divas BBP28 proteīna struktūras - viena pilna garuma un otra saīsinātai proteīna sekvencei, kas nesatur nestrukturēto 27 aa garo N gala segmentu. Strukturēto BBP28 daļu veido piecas α-spirāles un 14 aa gara virkne C-galā, kas kovalenti piesaistīta ar disulfīda saiti pie 4. un 5. α-spirāli savienoj…
Identification of Lactobacilli from Deep Carious Lesions by Means of Species-Specific PCR and MALDI-TOF Mass Spectrometry
2014
SUMMARY Background: The aim of the present study was to compare MALDI-TOF results for the identification of 87 lactobacilli, isolated from soft or hard carious dentin from 70 first molars of 7- to 8-year-old children with those obtained by species-specific PCR. Methods: The 87 isolates were analyzed by MALDI-TOF MS (Microflex LT, MALDI Biotyper 3.0, Bruker Daltonik, Bremen, Germany), using a reference data base of 4110 strains including > 90 lactobacillus species. For the identification with species-specific PCR, oligonucleotide primers (16S rRNA) specific for L. casei, L. paracasei, L. rhamnosus, L. gasseri, L. plantarum, and L. acidophilus were used; type strains served as controls. The P…