Created with SnapotherTCCAZyme11398279641945592699083879785111831258113979


PUL ID

PUL0204

PubMed

25841008, Appl Environ Microbiol. 2015 Jun 15;81(12):3973-83. doi: 10.1128/AEM.00149-15. Epub 2015 Apr 3.
18996345, Cell Host Microbe. 2008 Nov 13;4(5):447-57. doi: 10.1016/j.chom.2008.09.007.

Characterization method

qPCR,thin-layer chromatography,substrate binding assay

Genomic accession number

NC_004663.1

Nucelotide position range

4800873-4814851

Substrate

starch

Loci

BT_3698-BT_3704

Species

Bacteroides thetaiotaomicron/818

Degradation or Biosynthesis

degradation

Cluster number

1

Gene name

Gene position

Gene type

Found by CGCFinder?

- 1 - 2079 (-) CAZyme: GH13_36 Yes
- 2189 - 3646 (-) other Yes
- 3672 - 4835 (-) other Yes
susD 4870 - 6525 (-) TC: gnl|TC-DB|Q8A1G2|8.A.46.1.1 Yes
- 6547 - 9558 (-) TC: gnl|TC-DB|Q45780|1.B.14.6.1 Yes
- 9713 - 11929 (-) CAZyme: GH97 Yes
- 12126 - 13979 (-) CAZyme: GH13_46 Yes

PUL ID

PUL0204

PubMed

25841008, Appl Environ Microbiol. 2015 Jun 15;81(12):3973-83. doi: 10.1128/AEM.00149-15. Epub 2015 Apr 3.

Title

Differential Metabolism of Exopolysaccharides from Probiotic Lactobacilli by the Human Gut Symbiont Bacteroides thetaiotaomicron.

Author

Lammerts van Bueren A, Saraf A, Martens EC, Dijkhuizen L

Abstract

Probiotic microorganisms are ingested as food or supplements and impart positive health benefits to consumers. Previous studies have indicated that probiotics transiently reside in the gastrointestinal tract and, in addition to modulating commensal species diversity, increase the expression of genes for carbohydrate metabolism in resident commensal bacterial species. In this study, it is demonstrated that the human gut commensal species Bacteroides thetaiotaomicron efficiently metabolizes fructan exopolysaccharide (EPS) synthesized by probiotic Lactobacillus reuteri strain 121 while only partially degrading reuteran and isomalto/malto-polysaccharide (IMMP) alpha-glucan EPS polymers. B. thetaiotaomicron metabolized these EPS molecules via the activation of enzymes and transport systems encoded by dedicated polysaccharide utilization loci specific for beta-fructans and alpha-glucans. Reduced metabolism of reuteran and IMMP alpha-glucan EPS molecules may be due to reduced substrate binding by components of the starch utilization system (sus). This study reveals that microbial EPS substrates activate genes for carbohydrate metabolism in B. thetaiotaomicron and suggests that microbially derived carbohydrates provide a carbohydrate-rich reservoir for B. thetaiotaomicron nutrient acquisition in the gastrointestinal tract.

PubMed

18996345, Cell Host Microbe. 2008 Nov 13;4(5):447-57. doi: 10.1016/j.chom.2008.09.007.

Title

Mucosal glycan foraging enhances fitness and transmission of a saccharolytic human gut bacterial symbiont.

Author

Martens EC, Chiang HC, Gordon JI

Abstract

The distal human gut is a microbial bioreactor that digests complex carbohydrates. The strategies evolved by gut microbes to sense and process diverse glycans have important implications for the assembly and operation of this ecosystem. The human gut-derived bacterium Bacteroides thetaiotaomicron forages on both host and dietary glycans. Its ability to target these substrates resides in 88 polysaccharide utilization loci (PULs), encompassing 18% of its genome. Whole genome transcriptional profiling and genetic tests were used to define the mechanisms underlying host glycan foraging in vivo and in vitro. PULs that target all major classes of host glycans were identified. However, mucin O-glycans are the principal host substrate foraged in vivo. Simultaneous deletion of five genes encoding ECF-sigma transcription factors, which activate mucin O-glycan utilization, produces defects in bacterial persistence in the gut and in mother-to-offspring transmission. Thus, PUL-mediated glycan catabolism is an important component in gut colonization and may impact microbiota ecology.