Fig. 4

The rapid co-evolution of the ingested probiotic and resident gut microbiota of humans and mice within 28 days. A The Euclidean distance based on the number of SNPs identified from day 0 to other time points during the probiotic colonization in human and mouse models. It strongly indicated an intensive evolutionary response in resident microbiota due to probiotic intake. B The distribution of the mutations identified in the candidate probiotic Lp082 and resident gut microbiota from the probiotic and placebo group in both human and mouse models. Each dot in the boxplot represents the number of SNPs that occurred on a microbial strain in the gut of a host subject as compared to that on day 0. The “GM” is the abbreviation of “gut microbiota”. C The ecological relationship with Lp082 determined the number of SNPs that occurred on a resident microbial strain. Overall, the number of SNPs of probiotic “competitors” (orange, such as Bacteroides spp. and Bifidobacterium spp.) was significantly greater than that of “non-competitors” of this probiotic (orchid) or this probiotics (green) in the human model. In the mouse model, the adaptive mutations occurring in those probiotic competitors were one to two orders of magnitude more than those identified in the probiotics over the 28-day sampling period. The least mutations were identified in the placebo group (blue line). D The heat map indicates the median number of SNPs identified in each microbial species at day 14 and day 28 in each host group compared to day 0. Asterisks: statistical significance (*p < 0.05, **p < 0.01, ***p < 0.001)