A5059560909- Enzyme Production and Characterization
- Biofuel production and bioconversion
- Polysaccharides and Plant Cell Walls
- Microbial Metabolites in Food Biotechnology
- Glycosylation and Glycoproteins Research
- Carbohydrate Chemistry and Synthesis
- Enzyme Catalysis and Immobilization
- Enzyme Structure and Function
- Probiotics and Fermented Foods
- Studies on Chitinases and Chitosanases
- Digestive system and related health
- Legume Nitrogen Fixing Symbiosis
- Microbial Metabolic Engineering and Bioproduction
- Genomics and Phylogenetic Studies
- Gut microbiota and health
- Advanced Cellulose Research Studies
- Biochemical and Molecular Research
- Bacterial Genetics and Biotechnology
- Cancer Research and Treatments
- Polysaccharides Composition and Applications
- Microbial Natural Products and Biosynthesis
- Animal Genetics and Reproduction
- Diet, Metabolism, and Disease
- Food composition and properties
- Polyamine Metabolism and Applications
Hôpital de la Timone
2024
Newcastle University
2011-2021
Seiko Holdings (Japan)
2017
University of Maryland, Baltimore County
2017
University of Georgia
2009-2015
Newcastle upon Tyne Hospital
2015
Centre National de la Recherche Scientifique
2014
King Abdulaziz University
2014
Aix-Marseille Université
2014
Weizmann Institute of Science
2013
Symbiotic bacteria inhabiting the human gut have evolved under intense pressure to utilize complex carbohydrates, primarily plant cell wall glycans in our diets. These polysaccharides are not digested by enzymes, but processed absorbable short chain fatty acids bacteria. The Bacteroidetes, one of two dominant bacterial phyla adult gut, possess broad glycan-degrading abilities. species use a series membrane protein complexes, termed Sus-like systems, for catabolism many carbohydrates....
Abstract The structure of the human gut microbiota is controlled primarily through degradation complex dietary carbohydrates, but extent to which carbohydrate breakdown products are shared between members unclear. We show here, using xylan as a model, that sharing carbohydrates by key microbiota, such Bacteroides ovatus , dependent on complexity target glycan. Characterization extensive degrading apparatus expressed B. reveals polysaccharide significantly more than previous models suggested,...
How the diverse polysaccharides present in plant cell walls are assembled and interlinked into functional composites is not known detail. Here, using two novel monoclonal antibodies a carbohydrate-binding module directed against mannan group of hemicellulose wall polysaccharides, we show that molecular recognition intact severely restricted. In secondary walls, esterification can prevent probe epitopes/ligands, detection mannans primary be effectively blocked by presence pectic...
The Polysaccharide Utilization Loci (PUL) database was launched in 2015 to present PUL predictions ∼70 Bacteroidetes species isolated from the human gastrointestinal tract, as well PULs derived experimental data reported literature. In 2018 PULDB offers access 820 genomes, sampled various environments and covering a much wider taxonomical range. A Krona dynamic chart set up facilitate browsing through taxonomy. Literature surveys now allows presentation of most recent (i) repertoires deduced...
Abstract Motivation: A bacterial polysaccharide utilization locus (PUL) is a set of physically linked genes that orchestrate the breakdown specific glycan. PULs are prevalent in Bacteroidetes phylum and key to digestion complex carbohydrates, notably by human gut microbiota. given genome can encode dozens different whose boundaries precise gene content difficult predict. Results: Here, we present fully automated approach for PUL prediction using genomic context domain annotation alone. By...
CAZypedia was initiated in 2007 to create a comprehensive, living encyclopedia of the carbohydrate-active enzymes (CAZymes) and associated carbohydrate-binding modules involved synthesis, modification degradation complex carbohydrates. is closely connected with actively curated CAZy database, which provides sequence-based foundation for biochemical, mechanistic structural characterization these diverse proteins. Now celebrating its 10th anniversary online, successful example dynamic,...
To investigate the mode of action cellulose-binding domains (CBDs), Type II CBD from Pseudomonas fluorescenssubsp. cellulosaxylanase A (XYLACBD) and cellulase E (CELECBD) were expressed as individual entities or fused to catalytic domain a Clostridium thermocellumendoglucanase (EGE). The two CBDs exhibited similar Ka values for bacterial microcrystalline cellulose (CELECBD, 1.62×106 M-1; XYLACBD, 1.83×106 M-1) acid-swollen 1.66×106 1.73×106 M-1). NMR spectra XYLACBD titrated with...
Plant cell walls are degraded by glycoside hydrolases that often contain noncatalytic carbohydrate-binding modules (CBMs), which potentiate degradation. There currently 11 sequence-based cellulose-directed CBM families; however, the biological significance of structural diversity displayed these protein is uncertain. Here we interrogate capacity eight cellulose-binding CBMs to bind walls. These target crystalline cellulose (type A) and located in families 1, 2a, 3a, 10 (CBM1, CBM2a, CBM3a,...
The complete nucleotide sequence of the Pseudomonas fluorescens subsp. cellulosa xynB gene, encoding an endo-beta-1,4-xylanase (xylanase B; XYLB) has been determined. structural gene consists open reading frame (ORF) 1775 bp coding for a protein Mr 61,000. A second ORF (xynC) 1712 bp, which starts 148 downstream xynB, encodes protein, designated xylanase C (XYLC), 59,000. XYLB hydrolyses oat spelt xylan to xylobiose and xylose, whereas XYLC releases only arabinose from same substrate. Thus...
ABSTRACT The plant cell wall, which consists of a highly complex array interconnecting polysaccharides, is the most abundant source organic carbon in biosphere. Microorganisms that degrade wall synthesize an extensive portfolio hydrolytic enzymes display molecular architectures. To unravel intricate repertoire wall-degrading synthesized by saprophytic soil bacterium Cellvibrio japonicus , we sequenced and analyzed its genome, predicts contains complete required to storage polysaccharides....
The hemicellulose 4- O -methyl glucuronoxylan is one of the principle components present in secondary cell walls eudicotyledonous plants. However, biochemical mechanisms leading to formation this polysaccharide and effects modulating its structure on physical properties wall are poorly understood. We have identified functionally characterized an Arabidopsis methyltransferase (GXMT) that catalyzes -methylation glucuronic acid substituents polysaccharide. AtGXMT1, which was previously...
Plant cell walls are constructed from a diversity of polysaccharide components. Molecular probes directed to structural elements these polymers required assay structures in situ, and determine polymer roles the context wall biology. Here, we report on isolation characterization three rat monoclonal antibodies that 1,5-linked arabinans related polymers. LM13, LM16 LM17, together with LM6, constitute set can detect differing aspects arabinan within walls. Each binds strongly isolated sugar...
Noncatalytic carbohydrate binding modules (CBMs) are components of glycoside hydrolases that attack generally inaccessible substrates. CBMs mediate a two- to fivefold elevation in the activity endo-acting enzymes, likely through increasing concentration appended enzymes vicinity substrate. The function exo-acting is unclear because their typical endo-binding mode would not fulfill targeting role. Here we show Bacillus subtilis β-fructosidase SacC, which specifically hydrolyses levan,...