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Citation
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HERO ID
2283986
Reference Type
Journal Article
Title
Summer Meeting 2013: growth and physiology of bifidobacteria
Author(s)
De Vuyst, L; Moens, F; Selak, M; Rivière, A; Leroy, F
Year
2014
Is Peer Reviewed?
Yes
Journal
Journal of Applied Microbiology
ISSN:
1364-5072
EISSN:
1365-2672
Volume
116
Issue
3
Page Numbers
477-491
Language
English
PMID
24314205
DOI
10.1111/jam.12415
URL
https://onlinelibrary.wiley.com/doi/10.1111/jam.12415
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Abstract
Bifidobacteria are a minor fraction of the human colon microbiota with interesting properties for carbohydrate degradation. Monosaccharides such as glucose and fructose are degraded through the bifid shunt, a dedicated pathway involving phosphoketolase activity. Its stoechiometry learns that three moles of acetate and two moles of lactate are produced per two moles of glucose or fructose that are degraded. However, deviations from this 3 : 2 ratio occur, depending on the rate of substrate consumption. Slower growth rates favour the production of acetate and pyruvate catabolites (such as formate) at the cost of lactate. Interestingly, bifidobacteria are capable to degrade inulin-type fructans (ITF) (oligofructose and inulin) and arabinoxylan-oligosaccharides (AXOS). Beta-fructofuranosidase activity enables bifidobacteria to degrade ITF. However, this property is strain-dependent. Some strains consume both fructose and oligofructose, with different preferences and degradation rates. Small oligosaccharides (degree of polymerization or DP of 2-7) are taken up, in a sequential order, indicating intracellular degradation and as such giving these bacteria a competitive advantage towards other inulin-type fructan degraders such as lactobacilli, bacteroides and roseburias. Other strains consume long fractions of oligofructose and inulin. Exceptionally, oligosaccharides with a DP of up to 20 (long-chain inulin) are consumed by specific strains. Also, the degradation of AXOS by α-arabinofuranosidase and β-xylosidase is strain-dependent. Particular strains consume the arabinose substituents, whether or not together with a consumption of the xylose backbones of AXOS, either up to xylotetraose or higher and either extra- or intracellularly. The production of high amounts of acetate that accompanies inulin-type fructan degradation by bifidobacteria cross-feeds other colon bacteria involved in the production of butyrate. However, bifidobacterial strain-dependent differences in prebiotic degradation indicate the existence of niche-specific adaptations and hence mechanisms to avoid competition among each other and to favour coexistence with other colon bacteria.
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IRIS
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n-Butanol
Database searches
Pubmed
Database Searches - March 2014 (private)
Pubmed - 3/2014
Excluded (not pertinent)
Not chemical specific
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