PUL ID

PUL0357

PubMed

16968696, J Biol Chem. 2006 Nov 24;281(47):36269-79. doi: 10.1074/jbc.M606509200. Epub 2006 Sep 12.

Characterization method

microarray

Genomic accession number

AE015928.1

Nucelotide position range

1061861-1068345

Substrate

arabinan,xylan,levan,pectin,rhamnogalacturonan

Loci

BT_0865-BT_0867

Species

Bacteroides thetaiotaomicron/818

Degradation or Biosynthesis

degradation

Gene Name

Locus Tag

Protein ID

Gene Position

GenBank Contig Range

EC Number

- BT_0865 AAO75972.1 0 - 1323 (-) AE015928.1:1061861-1063184 -
- BT_0866 AAO75973.1 1353 - 3252 (-) AE015928.1:1063214-1065113 -
- BT_0867 AAO75974.1 3272 - 6485 (-) AE015928.1:1065133-1068346 -

Cluster number

1

Gene name

Gene position

Gene type

Found by CGCFinder?

- 1 - 1323 (-) CAZyme: CBM32 Yes
- 1354 - 3252 (-) other Yes
- 3273 - 6485 (-) TC: gnl|TC-DB|Q45780|1.B.14.6.1 Yes

PUL ID

PUL0357

PubMed

16968696, J Biol Chem. 2006 Nov 24;281(47):36269-79. doi: 10.1074/jbc.M606509200. Epub 2006 Sep 12.

Title

Functional genomic and metabolic studies of the adaptations of a prominent adult human gut symbiont, Bacteroides thetaiotaomicron, to the suckling period.

Author

Bjursell MK, Martens EC, Gordon JI

Abstract

The adult human gut microbiota is dominated by two divisions of Bacteria, the Bacteroidetes and the Firmicutes. Assembly of this community begins at birth through processes that remain largely undefined. In this report, we examine the adaptations of Bacteroides thetaiotaomicron, a prominent member of the adult distal intestinal microbiota, during the suckling and weaning periods. Germ-free NMRI mice were colonized at birth from their gnotobiotic mothers, who harbored this anaerobic Gram-negative saccharolytic bacterium. B. thetaiotaomicron was then harvested from the ceca of these hosts during the suckling period (postnatal day 17) and after weaning (postnatal day 30). Whole genome transcriptional profiles were obtained at these two time points using custom B. thetaiotaomicron GeneChips. Transcriptome-based in silico reconstructions of bacterial metabolism and gas chromatography-mass spectrometry and biochemical assays of carbohydrate utilization in vivo indicated that in the suckling gut B. thetaiotaomicron prefers host-derived polysaccharides, as well as mono- and oligosaccharides present in mother's milk. After weaning, B. thetaiotaomicron expands its metabolism to exploit abundant, plant-derived dietary polysaccharides. The bacterium's responses to postnatal alterations in its nutrient landscape involve expression of gene clusters encoding environmental sensors, outer membrane proteins involved in binding and import of glycans, and glycoside hydrolases. These expression changes are interpreted in light of a phylogenetic analysis that revealed unique expansions of related polysaccharide utilization loci in three human alimentary tract-associated Bacteroidetes, expansions that likely reflect the evolutionary adaptations of these species to different nutrient niches.