Human gut Bacteroidetes can utilize yeast mannan through a selfish mechanism.
Nature
; 517(7533): 165-169, 2015 Jan 08.
Article
em En
| MEDLINE
| ID: mdl-25567280
ABSTRACT
Yeasts, which have been a component of the human diet for at least 7,000 years, possess an elaborate cell wall α-mannan. The influence of yeast mannan on the ecology of the human microbiota is unknown. Here we show that yeast α-mannan is a viable food source for the Gram-negative bacterium Bacteroides thetaiotaomicron, a dominant member of the microbiota. Detailed biochemical analysis and targeted gene disruption studies support a model whereby limited cleavage of α-mannan on the surface generates large oligosaccharides that are subsequently depolymerized to mannose by the action of periplasmic enzymes. Co-culturing studies showed that metabolism of yeast mannan by B. thetaiotaomicron presents a 'selfish' model for the catabolism of this difficult to breakdown polysaccharide. Genomic comparison with B. thetaiotaomicron in conjunction with cell culture studies show that a cohort of highly successful members of the microbiota has evolved to consume sterically-restricted yeast glycans, an adaptation that may reflect the incorporation of eukaryotic microorganisms into the human diet.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Leveduras
/
Trato Gastrointestinal
/
Bacteroidetes
/
Mananas
/
Modelos Biológicos
Limite:
Animals
/
Female
/
Humans
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Male
Idioma:
En
Revista:
Nature
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Reino Unido