PUL ID

PUL0559

PubMed

28329766, Nature. 2017 Apr 6;544(7648):65-70. doi: 10.1038/nature21725. Epub 2017 Mar 22.

Characterization method

gene deletion mutant and growth assay, growth assay, enzyme activity assay

Genomic accession number

AE015928.1

Nucelotide position range

4749697-4766546

Substrate

rhamnogalacturonan

Loci

BT3662-BT3673

Species

Bacteroides thetaiotaomicron/818

Degradation or Biosynthesis

degradation

Cluster number

1

Gene name

Gene position

Gene type

Found by CGCFinder?

- 1 - 1386 (+) CAZyme: CBM32|GH43_34 Yes
- 1641 - 3002 (+) CAZyme: GH43_10 Yes
- 3014 - 4930 (+) CAZyme: GH97 Yes
- 5049 - 6692 (+) CAZyme: GH29 Yes
- 6704 - 7093 (+) other Yes
- 7170 - 8030 (-) TF: DBD-Pfam|HTH_AraC,DBD-Pfam|HTH_AraC,DBD-SUPERFAMILY|0036286,DBD-SUPERFAMILY|0035607 Yes
- 8247 - 8981 (+) other Yes
- 9062 - 9652 (+) other Yes
- 9652 - 12792 (+) TC: gnl|TC-DB|Q45780|1.B.14.6.1 Yes
- 12817 - 14892 (+) CDS No
- 14924 - 15883 (+) CDS No
- 15999 - 16850 (+) CDS No

PUL ID

PUL0559

PubMed

28329766, Nature. 2017 Apr 6;544(7648):65-70. doi: 10.1038/nature21725. Epub 2017 Mar 22.

Title

Complex pectin metabolism by gut bacteria reveals novel catalytic functions.

Author

Ndeh D, Rogowski A, Cartmell A, Luis AS, Basle A, Gray J, Venditto I, Briggs J, Zhang X, Labourel A, Terrapon N, Buffetto F, Nepogodiev S, Xiao Y, Field RA, Zhu Y, O'Neil MA, Urbanowicz BR, York WS, Davies GJ, Abbott DW, Ralet MC, Martens EC, Henrissat B, Gilbert HJ

Abstract

The metabolism of carbohydrate polymers drives microbial diversity in the human gut microbiota. It is unclear, however, whether bacterial consortia or single organisms are required to depolymerize highly complex glycans. Here we show that the gut bacterium Bacteroides thetaiotaomicron uses the most structurally complex glycan known: the plant pectic polysaccharide rhamnogalacturonan-II, cleaving all but 1 of its 21 distinct glycosidic linkages. The deconstruction of rhamnogalacturonan-II side chains and backbone are coordinated to overcome steric constraints, and the degradation involves previously undiscovered enzyme families and catalytic activities. The degradation system informs revision of the current structural model of rhamnogalacturonan-II and highlights how individual gut bacteria orchestrate manifold enzymes to metabolize the most challenging glycan in the human diet.