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Bacterial Biomarkers (bacterial + biomarker)
Selected AbstractsCover Picture: Electrophoresis 6'09ELECTROPHORESIS, Issue 6 2009Article first published online: 23 MAR 200 Issue no. 6 is an Emphasis Issue with 7 articles on various aspects of "Proteins and Proteomics" while the remaining 15 articles are arranged into 4 different parts on "Genotyping and Sequencing", "Enantioseparations", "Non Aqueous CE", and "Methodologies and Applications." Selected articles are: Differences in protein distribution between human plasma preparations, EDTA-plasma and heparin-plasma, analyzed by non-denaturing micro-2-DE and MALDI-MS PMF 2-DE and MS analysis of key proteins in the adhesion of Lactobacillus plantarum, a first step toward early selection of probiotics based on bacterial biomarkers Centrifugal methods and devices for rapid in-gel digestion of proteins [source] On-line sample preconcentration with chemical derivatization of bacterial biomarkers by capillary electrophoresis: A dual strategy for integrating sample pretreatment with chemical analysisELECTROPHORESIS, Issue 21 2005Adam S. Ptolemy Abstract Simple, selective yet sensitive methods to quantify low-abundance bacterial biomarkers derived from complex samples are required in clinical, biological, and environmental applications. In this report, a new strategy to integrate sample pretreatment with chemical analysis is investigated using on-line preconcentration with chemical derivatization by CE and UV detection. Single-step enantioselective analysis of muramic acid (MA) and diaminopimelic acid (DAP) was achieved by CE via sample enrichment by dynamic pH junction with ortho -phthalaldehyde/N -acetyl- L -cysteine labeling directly in-capillary. The optimized method resulted in up to a 100-fold enhancement in concentration sensitivity compared to conventional off-line derivatization procedures. The method was also applied toward the detection of micromolar levels of MA and DAP excreted in the extracellular medium of Escherichia coli bacterial cell cultures. On-line preconcentration with chemical derivatization by CE represents a unique approach for conducting rapid, sensitive, and high-throughput analyses of other classes of amino acid and amino sugar metabolites with reduced sample handling, where the capillary functions simultaneously as a concentrator, microreactor, and chiral selector. [source] Quantification of effects of season and nitrogen supply on tree below-ground carbon transfer to ectomycorrhizal fungi and other soil organisms in a boreal pine forestNEW PHYTOLOGIST, Issue 2 2010Mona N. Högberg Summary ,The flux of carbon from tree photosynthesis through roots to ectomycorrhizal (ECM) fungi and other soil organisms is assumed to vary with season and with edaphic factors such as nitrogen availability, but these effects have not been quantified directly in the field. ,To address this deficiency, we conducted high temporal-resolution tracing of 13C from canopy photosynthesis to different groups of soil organisms in a young boreal Pinus sylvestris forest. ,There was a 500% higher below-ground allocation of plant C in the late (August) season compared with the early season (June). Labelled C was primarily found in fungal fatty acid biomarkers (and rarely in bacterial biomarkers), and in Collembola, but not in Acari and Enchytraeidae. The production of sporocarps of ECM fungi was totally dependent on allocation of recent photosynthate in the late season. There was no short-term (2 wk) effect of additions of N to the soil, but after 1 yr, there was a 60% reduction of below-ground C allocation to soil biota. ,Thus, organisms in forest soils, and their roles in ecosystem functions, appear highly sensitive to plant physiological responses to two major aspects of global change: changes in seasonal weather patterns and N eutrophication. [source] Optimization of quartz tube pyrolysis atmospheric pressure ionization mass spectrometry for the generation of bacterial biomarkersRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 18 2001Ashish Tripathi Experimental procedures were investigated to improve the efflux of biomolecule pyrolyzates from quartz tube pyrolysis under atmospheric pressure ionization mass spectrometry conditions. Heating regimes, airflows, and ion focusing parameters were optimized to increase the informative mass spectral signals generated from the pyrolysis of Gram-positive bacterial spores and vegetative cells. Dipicolinic acid (DPA) is found in 5,15% by weight in Gram-positive Bacillus spores, and the parameter optimization procedures provided an intense mass spectral signature of the m/z 168 protonated DPA molecule with a minimization of pyrolytic and ionization fragments. Moreover, mass spectral information from the optimization protocols yielded peaks and mass patterns characteristic of DNA and RNA nitrogen bases, protein diketopiperazines, and amino sugars. Copyright © 2001 John Wiley & Sons, Ltd. [source] | ||||||||||