The commensal infant gut meta-mobilome as a potential reservoir for persistent multidrug resistance integrons

Despite the accumulating knowledge on the development and establishment of the gut microbiota, its role as a reservoir for multidrug resistance is not well understood. This study investigated the prevalence and persistence patterns of an integrase gene (int1), used as a proxy for integrons (which often carry multiple antimicrobial resistance genes), in the fecal microbiota of 147 mothers and their children sampled longitudinally from birth to 2 years. The study showed the int1 gene was detected in 15% of the study population, and apparently more persistent than the microbial community structure itself. We found int1 to be persistent throughout the first two years of life, as well as between mothers and their 2-year-old children. Metagenome sequencing revealed integrons in the gut meta-mobilome that were associated with plasmids and multidrug resistance. In conclusion, the persistent nature of integrons in the infant gut microbiota makes it a potential reservoir of mobile multidrug resistance

Potential association of vacuum cleaning frequency with an altered gut microbiota in pregnant women and their 2-year-old children

Background: Westernized lifestyle and hygienic behavior have contributed to dramatic changes in the human-associated microbiota. This particularly relates to indoor activities such as house cleaning. We therefore investigated the associations between washing and vacuum cleaning frequency and the gut microbiota composition in a large longitudinal cohort of mothers and their children. The gut microbiota composition was determined using 16S ribosomal RNA (rRNA) gene Illumina deep sequencing. Results: We found that high vacuum cleaning frequency about twice or more a week was associated with an altered gut microbiota composition both during pregnancy and for 2-year-old children, while there were no associations with house washing frequency. In total, six Operational Taxonomic Units (OTUs) showed significant False Discovery Rate (FDR) corrected associations with vacuum cleaning frequency for mothers (two positive and four negative) and five for 2-year-old children (four positive and one negative). For mothers and the 2-year-old children, OTUs among the dominant microbiota (average >5 %) showed correlation to vacuum cleaning frequency, with an increase in Faecalibacterium prausnitzii for mothers (p = 0.013, FDR corrected), and Blautia sp. for 2-year children (p = 0.012, FDR corrected). Conclusions: Bacteria showing significant associations are among the dominant gut microbiota, which may indicate indirect immunomodulation of the gut microbiota possibly through increased allergen (dust mites) exposure as a potential mechanism. However, further exploration is needed to unveil mechanistic details

Effect of probiotics in prevention of atopic dermatitis is dependent on the intrinsic microbiota at early infancy

Although a link between probiotic intervention and reduction in atopic disease has been documented, no consistent associations with microbiota has yet been established. Here we have conducted an extensive analysis of the microbiota from more than 250 mother child pairs from a probiotic intervention cohort, where we previously have shown 40 % reduction in atopic dermatitis. Within the probiotic intervention group at the age of 10 days we found that the atopic children had a deviating microbiota (p = 0.028, BH-FDR corrected Kruskal Wallis) with high levels (> 10 %) of a bacterium related to Bifidobacterium dentium (p=0.039, BHFDR corrected Chi-square). Based on these findings, we propose a model with two groups of children where the group responding to probiotic intervention, has gut microbiota related to that of non-atopic children; while the non-responding group has a divergent microbiota at the age of 10 days with overrepresented amounts of B. dentium. In conclusion, our results support the importance of early colonization for prevention of diseases developing later in life, with potential intervention effects being dependent on the intrinsic microbiota.Peer reviewe