Institution
University of Avignon
Education•Avignon, Provence-Alpes-Côte-d'Azur, France•
About: University of Avignon is a education organization based out in Avignon, Provence-Alpes-Côte-d'Azur, France. It is known for research contribution in the topics: Population & Speaker recognition. The organization has 1526 authors who have published 3766 publications receiving 88928 citations.
Topics: Population, Speaker recognition, Context (language use), Extraction (chemistry), Wireless network
Papers published on a yearly basis
Papers
More filters
••
TL;DR: This study shows the existence of six PULs devoted to pectin degradation by B. xylanisolvens, one of them being particularly important in this function, hence, this species deploys a very complex enzymatic machinery that probably reflects the structural complexity of pECTin.
Abstract: Diet and particularly dietary fibres have an impact on the gut microbiome and play an important role in human health and disease. Pectin is a highly consumed dietary fibre found in fruits and vegetables and is also a widely used additive in the food industry. Yet there is no information on the effect of pectin on the human gut microbiome. Likewise, little is known on gut pectinolytic bacteria and their enzyme systems. This study was undertaken to investigate the mechanisms of pectin degradation by the prominent human gut symbiont Bacteroides xylanisolvens. Transcriptomic analyses of B. xylanisolvens XB1A grown on citrus and apple pectins at mid- and late-log phases highlighted six polysaccharide utilization loci (PUL) that were overexpressed on pectin relative to glucose. The PUL numbers used in this report are those given by Terrapon et al. (Bioinformatics 31(5):647-55, 2015) and found in the PUL database: http://www.cazy.org/PULDB/
. Based on their CAZyme composition, we propose that PUL 49 and 50, the most overexpressed PULs on both pectins and at both growth phases, are involved in homogalacturonan (HG) and type I rhamnogalacturonan (RGI) degradation, respectively. PUL 13 and PUL 2 could be involved in the degradation of arabinose-containing side chains and of type II rhamnogalacturonan (RGII), respectively. Considering that HG is the most abundant moiety (>70 %) within pectin, the importance of PUL 49 was further investigated by insertion mutagenesis into the susC-like gene. The insertion blocked transcription of the susC-like and the two downstream genes (susD-like/FnIII). The mutant showed strong growth reduction, thus confirming that PUL 49 plays a major role in pectin degradation. This study shows the existence of six PULs devoted to pectin degradation by B. xylanisolvens, one of them being particularly important in this function. Hence, this species deploys a very complex enzymatic machinery that probably reflects the structural complexity of pectin. Our findings also highlight the metabolic plasticity of B. xylanisolvens towards dietary fibres that contributes to its competitive fitness within the human gut ecosystem. Wider functional and ecological studies are needed to understand how dietary fibers and especially plant cell wall polysaccharides drive the composition and metabolism of the fibrolytic and non-fibrolytic community within the gut microbial ecosystem.
44 citations
••
TL;DR: Results suggested that long-term exposure of honeybees to cypermethrin-contaminated diets at concentrations not immediately lethal to worker adults may cause significant hidden damage to colonies.
44 citations
••
TL;DR: A new RNN called “Parsimonious Memory Unit” (PMU) is proposed based on the strong assumption that short and long-term dependencies are related and that the role of each hidden neuron has to be different to better handle term dependencies.
44 citations
••
TL;DR: In this paper, sampling of soil wood charcoals at high spatial resolution produces new evidence concerning the presence of chalk grassland before or during the Neolithic, Bronze and Iron Ages.
Abstract: Questions: (i) Can sampling of soil wood charcoals at high spatial resolution produce new evidence concerning the presence of chalk grassland before or during the Neolithic, Bronze and Iron Ages? (ii) Are there correlations between vegetation history and archeological data during these periods at this particular site?
44 citations
••
TL;DR: A new class of nonionic hybrid hydrofluoro amphiphiles derived from tris(hydroxymethyl)aminomethane (THAM) exhibit neither detergency toward cell membranes nor membrane protein denaturation.
44 citations
Authors
Showing all 1574 results
Name | H-index | Papers | Citations |
---|---|---|---|
Peter J. Diggle | 85 | 518 | 40325 |
Frédéric Baret | 73 | 289 | 25453 |
Farid Chemat | 71 | 339 | 18533 |
Eitan Altman | 60 | 637 | 16760 |
Mathilde Causse | 56 | 122 | 11973 |
Giancarlo Cravotto | 54 | 484 | 13555 |
Montserrat Dueñas | 52 | 117 | 6401 |
Catherine M.G.C. Renard | 52 | 235 | 9183 |
Pierre Renault | 49 | 172 | 23844 |
Yves Le Conte | 48 | 155 | 7985 |
Christophe Nguyen-The | 47 | 122 | 7499 |
Olivier Ouari | 46 | 145 | 6231 |
Miguel A. Pappolla | 46 | 121 | 9864 |
Marie-Josèphe Amiot | 45 | 113 | 7893 |
Marie Weiss | 44 | 139 | 9955 |