Ontology highlight
ABSTRACT:
PROVIDER: PRJNA849974 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR19744881_1.fastq.gz | Fastqsanger.gz | |||
| SRR19744881_2.fastq.gz | Fastqsanger.gz |
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Similar Datasets
Project description:A new strain of xanthan-degrading bacteria identified as Cohnella sp. has been isolated from a xanthan thickener for food production. The strain was able to utilize xanthan as the only carbon source and reduce the viscosity of the xanthan-containing medium during cultivation. Xanthan hydrolytic activity was revealed by congo red staining after growth of the strain on agar plates containing xanthan. By analyzing the secretome of Cohnella sp. after growth on different media (lysogeny broth, glucose mineral medium, xanthan mineral medium), a xanthanase designated as CspXan9 was found and its gene was successfully expressed in Escherichia coli Rosetta2. CspXan9 could efficiently degrade the -1,4-glucan backbone of xanthan after previous removal of pyruvylated mannose residues from the ends of the native xanthan side chains by xanthan lyase treatment (XLT-xanthan). Compared with a known xanthanase from Paenibacillus nanensis, the modular xanthanase CspXan9 had a different module composition at the N- and C-terminal ends. High-performance anion-exchange chromatography (HPAEC-PAD) analysis revealed that the main putative end products released from XLT-xanthan by CspXan9 hydrolysis were tetrasaccharides. Deletion derivatives lacking some of the non-catalytic domains (CspXan9-C, CspXan9-N, CspXan9-C-N) were produced in E. coli to explore the functions of the N- and C-terminal regions of the enzyme. Enzyme assays with the purified deletion derivatives, which all contained the catalytic glycoside hydrolase family 9 (GH9) module, resulted in a range of specific activities on XLT-xanthan between 10.31 ± 0.29 U/mg (CspXan9-C) and 1.38 ± 0.05 U/mg (CspXan9-C-N). Mobility shift assays performed by native affinity polyacrylamide gel electrophoresis (NAPAGE) in the presence of different polysaccharides indicated that the C-terminal module of CspXan9 represents a novel carbohydrate-binding module of CBM66 with binding affinity for XLT-xanthan. The only previously known binding function of a member of the CBM66 family is exo-type binding to the non-reducing fructose ends of the -fructan polysaccharides inulin and levan.
2024-06-14 | PXD050379 | Pride
Project description:Study of the microbial diversity on diuron-degrading consortium.
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Project description:Xanthan is the most used polysaccharide of bacterial origin. There are many industrial applications for xanthan, especially in food products. The organism Xanthomonas campestris is commonly used for xanthan fermentation, but little is known about the xanthan synthesis mechanism on the proteome level. The study used a label-free LC-MS/MS method to investigate the protein shifts during a typical xanthan fermentation of 72 hours. Two thousand four hundred sixteen proteins were identified, representing 54.75 % of the 4413 entries in the reference database. One thousand seven hundred forty-nine proteins were measured in a quantifiable quality. The quality of the proteome data was examined by the abundance changes of the ribosomal proteins according to the growth phases. The phenotypic changes during the cultivation, especially processes known to be influencing or close related to xanthan production, were investigated by proteome analysis. These processes were nitrogen metabolism, sugar nucleotide metabolism, and xanthan synthesis. This study shows the abundance of changes in central metabolites during a xanthan fermentation of Xcc. The presented research provides crucial information for further biotechnological studies to improve xanthan production.
2024-05-24 | PXD041470 | Pride
Project description:Coal Degrading Microbial Consortium
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Project description:Degrading Bagasse Consortium Metagenome
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Project description:The diets of industrialized countries reflect the increasing use of processed foods, often with the inclusion of novel food additives. Xanthan gum is a complex polysaccharide with unique rheological properties that have established its use as a widespread stabilizer and thickening agent. Xanthan gum’s chemical structure is distinct from the host and dietary polysaccharides that are more commonly expected to transit the gastrointestinal tract, and little is known about its direct interaction with the gut microbiota, which plays a central role in digestion of other dietary fiber polysaccharides. Here, we show that the ability to digest xanthan gum is surprisingly common in industrialized human gut microbiomes and appears contingent on a single uncultured bacterium in the family Ruminococcaceae. Our data reveal that this primary degrader cleaves the xanthan gum backbone before processing the released oligosaccharides using additional enzymes. Surprisingly, some individuals harbor a Bacteroides intestinalis that is incapable of consuming polymeric xanthan gum but grows on oligosaccharide products generated by the Ruminococcaceae. Feeding xanthan gum to germfree mice colonized with a human microbiota containing the uncultured Ruminococcaceae supports the idea that this additive can drive expansion of this primary degrader along with exogenously introduced Bacteroides intestinalis. Our work demonstrates the existence of a potential xanthan gum food chain involving at least two members of different phyla of gut bacteria and provides an initial framework to understand how widespread consumption of a recently introduced food additive influences human microbiomes.
2022-02-28 | PXD031522 | Pride