Changes in the microbiota across life: the existence of a core of microbial taxa and decoupling taxa.

With the present work we intend to demonstrate: 1) the existence of a core of microbial taxa that are true mutualistic symbionts andare present throughout the life of the host and, 2) the existence of microbial taxa that are not responding to host demands, exposing a decoupling between these taxa and the human host. For that, thirty healthy volunteers from Valencian Community (Spain) were involved in this study. The cohort IAE was stablished with 10 Infants (I) 2-5 years old, 10 Adults (A), 25-45 years old, and 10 elderly (E) 65-85 years old. Eight fecal samples were collected from each volunteer separated by a month. For all samples, the metagenomic, 16S rRNA and metatranscriptomic analysis of the microbiota was carried out by Illumina NextSeq with 150 bp x2 chemistry (metagenomic and metareanscriptomic) or by Illumina Miseq (16S).