PUL ID

PUL0284

PubMed

23199239, Microb Biotechnol. 2013 Jan;6(1):67-79. doi: 10.1111/1751-7915.12011. Epub 2012 Dec 2.

Characterization method

microarray,high performance anion exchange chromatography,liquid chromatography and mass spectrometry

Genomic accession number

CP000303.1

Nucelotide position range

1928568-1934764

Substrate

galactooligosaccharide

Loci

bbr_1551-bbr_1553

Species

Bifidobacterium breve/1685

Degradation or Biosynthesis

degradation

Gene Name

Locus Tag

Protein ID

Gene Position

GenBank Contig Range

EC Number

lacS Bbr_1551 ABE96222.1 0 - 1482 (-) CP000303.1:1928568-1930050 -
lacZ6 Bbr_1552 ABE96223.1 1849 - 4987 (+) CP000303.1:1930417-1933555 3.2.1.23
- Bbr_1553 ABE96224.1 5186 - 6197 (-) CP000303.1:1933754-1934765 -

Cluster number

1

Gene name

Gene position

Gene type

Found by CGCFinder?

lacS 1 - 1482 (-) TC: gnl|TC-DB|Q9X761|2.A.2.2.3 Yes
lacZ6 1850 - 4987 (+) CAZyme: GH2 Yes
- 5187 - 6197 (-) TF: DBD-Pfam|LacI,DBD-SUPERFAMILY|0036955 No

PUL ID

PUL0284

PubMed

23199239, Microb Biotechnol. 2013 Jan;6(1):67-79. doi: 10.1111/1751-7915.12011. Epub 2012 Dec 2.

Title

Transcriptional and functional characterization of genetic elements involved in galacto-oligosaccharide utilization by Bifidobacterium breve UCC2003.

Author

O'Connell Motherway M, Kinsella M, Fitzgerald GF, van Sinderen D

Abstract

Several prebiotics, such as inulin, fructo-oligosaccharides and galacto-oligosaccharides, are widely used commercially in foods and there is convincing evidence, in particular for galacto-oligosaccharides, that prebiotics can modulate the microbiota and promote bifidobacterial growth in the intestinal tract of infants and adults. In this study we describe the identification and functional characterization of the genetic loci responsible for the transport and metabolism of purified galacto-oligosaccharides (PGOS) by Bifidobacterium breve UCC2003. We further demonstrate that an extracellular endogalactanase specified by several B. breve strains, including B. breve UCC2003, is essential for partial degradation of PGOS components with a high degree of polymerization. These partially hydrolysed PGOS components are presumed to be transported into the bifidobacterial cell via various ABC transport systems and sugar permeases where they are further degraded to galactose and glucose monomers that feed into the bifid shunt. This work significantly advances our molecular understanding of bifidobacterial PGOS metabolism and its associated genetic machinery to utilize this prebiotic.