References of "Matteotti, Christel"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailSelection and cultivation of hydrolytic microorganisms extracted from the digestive tract of the termite Reticulitermes santonensis (3DV.1.55)
Tarayre, Cédric ULg; Bauwens, Julien ULg; Matteotti, Christel ULg et al

Poster (2012, June 21)

Biofuel production can be based on the use of fermentable substrates issued from the hydrolysis of lignocellulosic biomass stemming from agricultural residues and by-products. However, such substrates are ... [more ▼]

Biofuel production can be based on the use of fermentable substrates issued from the hydrolysis of lignocellulosic biomass stemming from agricultural residues and by-products. However, such substrates are not easy to degrade. Enzymes (cellulases, xylanases, etc.) can be used for this purpose and pre-treatments can increase their action by providing more available extremities. The digestive tract of the termite Reticulitermes santonensis contains various microorganisms (bacteria, molds, protists) able to degrade the wood components. These microorganisms act as consortia, leading to a better hydrolysis than in the cow rumen. Our purpose is the isolation of microorganisms from termite guts in order to evaluate their potential for hydrolysis of lignocellulosic materials. This approach led us to isolate and to study a bacteria (Bacillus sp.) displaying a xylanase activity, a mold (Aspergillus sp.) displaying a cellulase activity and a chrysophyte (protist) displaying an amylase activity. [less ▲]

Detailed reference viewed: 49 (16 ULg)
Full Text
See detailChanges in termites feeding diets for gut micro-organisms selection and further cultivation
Bauwens, Julien ULg; Brasseur, Catherine ULg; Matteotti, Christel ULg et al

Poster (2011, October 02)

Termites gut may overcome important dietary perturbations, initial diversity acting as key point buffering effects on host, although termites possess their own enzymatic system. Some artificial diets ... [more ▼]

Termites gut may overcome important dietary perturbations, initial diversity acting as key point buffering effects on host, although termites possess their own enzymatic system. Some artificial diets permitted a simplification of the lower termites gut symbiotic system, which could be used as first step in symbionts isolation and cultivation. Preliminary assay of cultivation actually gave encouraging results. Proteomic proved to be suitable tool to investigate such a complex system. Nevertheless, for some symbionts very few genes are sequenced, which should lead to more targeted proteomic studies. Protein chromatography will allow to split up the proteome and more accurate analysis. [less ▲]

Detailed reference viewed: 48 (22 ULg)
See detailCaractérisation de la diversité des organismes symbiotiques et des activités glycosyl hydrolases dans le tube digestif de Reticulitermes santonensis (Feytaud) par une approche multidisciplinaire
Bauwens, Julien ULg; Matteotti, Christel ULg; Brognaux, Alison ULg et al

Scientific conference (2010, July 08)

Le bioéthanol cellulosique pourrait être une solution pour satisfaire le besoin croissant en énergie renouvelable. Actuellement, l’efficience de la transformation de la cellulose en sucres fermentescibles ... [more ▼]

Le bioéthanol cellulosique pourrait être une solution pour satisfaire le besoin croissant en énergie renouvelable. Actuellement, l’efficience de la transformation de la cellulose en sucres fermentescibles reste le principal facteur limitant. La recherche de nouvelles glycosyl hydrolases constitue une voie potentielle d’amélioration de la valorisation des composés ligno-cellulosiques. Trois types de glycosyl hydrolases sont généralement produites par les organismes capables d’utiliser efficacement ces composés : les endoglucanases, les exoglucanases/cellobiohydrolases, et les β-glucosidases. Dans les processus de digestion de la cellulose par les animaux, des organismes symbiotiques tels que des bactéries, des protistes et/ou des champignons sont fréquemment observés. Ces organismes contribuent en grande partie voir totalement à la production des complexes enzymatiques nécessaires. Chez les termites inférieures, comme notre modèle Reticulitermes santonensis (Feytaud), des protistes et des bactéries sont impliqués dans un système symbiotique complexe. Une étude multidisciplinaire est menée afin d’approfondir les rôles respectifs des différents groupes de symbiontes, via des approches « omiques », à savoir la protéomique (ESI-LC-MS-MS, 2D-SDS-PAGE couplée avec une analyse en spectrométrie de masse du type MALDI-TOF pour l’identification des protéines), la génomique (avec une approche métagénomique basée sur la construction d’une large banque de cDNA), la métabolomique (caractérisation des produits de dégradation de carbohydrates via une strategie LC-MS). De plus, l’isolation de microorganismes a également été employée dans la caractérisation de la diversité et de l’activité des glycosyl hydrolases chez R. santonensis. [less ▲]

Detailed reference viewed: 93 (37 ULg)
See detailIntegrated “omics” approaches to investigate the chemical aspects of symbiosis in termites and potential application in ligno-cellulosic use.
Bauwens, Julien ULg; Matteotti, Christel ULg; Brognaux, Alison ULg et al

Scientific conference (2010, May 05)

Cellulosic bioethanol could be one of the solutions to satisfy the increasing demand in renewable energy. The most limitative problem is the efficiency of cellulose transformation into fermentable sugars ... [more ▼]

Cellulosic bioethanol could be one of the solutions to satisfy the increasing demand in renewable energy. The most limitative problem is the efficiency of cellulose transformation into fermentable sugars. Investigations to select new glycosyl hydrolases are an interesting approach that constitutes a potential opportunity to improve the valorization of lignocellulosic materials. Three major types of glycosyl hydolases are generally produced by organism’s that are able to efficiently use cellulosic compounds: the endoglucanases, the exoglucanases/cellobiohydrolases and the β-glucosidases. In the ability to transform lignocellulosic materials by animals, symbioses are generally observed with a range of micro-organisms including bacteria, protists and/or fungi that largely (or completely) contribute to the production of the needed enzymatic complexes. In termites, such active enzymes are produced in the insect digestive tract, by the termite insect itself or by symbiotic organisms. Within lower termites gut, such as in our model Reticulitermes santonensis (Feytaud), protists and bacteria are associated and involved in a complex symbiotic system. To investigate the respective role of the insect and different groups of symbionts, multidisciplinary “omics” approaches were here developed including proteomics (ESI-LC-MS-MS, 2D-Dige gel coupled with MALDI-TOF mass spectrometry for protein identification), genomics (with a metagenomic approach based on large cDNA bank construction), metabolomics (LC-MS stragety for carbohydrate degradation product characterization). Moreover, microorganism isolation was used to investigate and characterize glycosyl hydrolases diversity and activity in R. santonensis. The integration of this broad range of “omics” techniques allowed characterizing the role of symbionts in insects in a fundamental approach and to invtigate the chemical ecology of xylophagous insects but also corresponding to an efficient way to promote the selection of efficient enzymatic activities to potentially produce biofuels based on the use of existing lignocellulosic materials. [less ▲]

Detailed reference viewed: 97 (28 ULg)