Microbial succession in the infant gut

M. Pilar Francino

Valencian Region Foundation for the Promotion of Health and Biomedical Research (FISABIO), Spain; francino_pil@gva.es

(Talk in English)

ATTENTION: En raison des mesures de restriction d’accès au Campus Triolet, les personnes extérieures à l’Université de Montpellier doivent venir munies de: AFFICHE IMPRIMÉE + UNE PIECE D'IDENTITÉ.

The human gut microbiota develops through a complex succession, which takes place mostly during infancy and has a major impact on life-long health through early interactions with metabolism and immunity. Recent results indicate that bacteria likely start colonization of the gut in utero, through a process that may be influenced by numerous maternal factors and affect long-term health. After birth, the individual patterns of gut colonization in healthy infants are enormously varied, but recognizable trends indicate that 1) succession occurs in two distinct phases, separated by the introduction of solid foods, 2) there is directional change towards the taxonomic and functional composition of the maternal microbiota, and 3) succession is well advanced, but not complete, by the one-year mark. Network analyses indicate that positive interactions among core genera contribute to their permanence, and to progressively establish a network similar to that of the adult. A substantial fraction of interactions occur between genera belonging to the same taxonomic groups. A positive interaction between the Bacteroidales genera Bacteroides and Prevotella, which dominate each of the two main adult enterotypes, is present up to the seven-months timepoint. Therefore, any competitive interactions that give rise to enterotype differentiation likely start at a later date.

Recent publications:

Valles, Y. et al. (2014) Microbial Succession in the Gut: Directional Trends of Taxonomic and Functional Change in a Birth Cohort of Spanish Infants. PLoS Genetics 10: e1004406.

Valles, Y. et al. (2012) Metagenomics and development of the gut microbiota in infants. Clinical microbiology and infection 18: SI21-26.