Dynamic changes of intestinal 16S rDNA metagenome in 5 infants

Abstract:

Objective To investigate the dynamic changes of intestinal 16S rDNA metagenome in healthy infants.Methods Seventeen fecal samples were collected at ages of 3 days, 1 month, 6 months and 1 year in 5 infants. Totalbacterial DNAs were extracted and submitted high throughout sequencing on the V6 viable region of 16S rDNA. Tagsand Operational Taxonomic Units (OTU) were then obtained and analysis of taxonomy, abundance and alpha diversitywere performed. Results In total 2 190.66 Mbp raw data in 17 samples were produced. The OTU numbers rangedfrom 36 to 308. The dominate phylum included Proteobacteria, Firmicutes and Bacteroidetes and Actinobacteria. The bacterial families >1% increased from only 2-4 per sample on day 3 to 7 at 1 or 6 months, 10 at 12 months. The averagenp Shannon and Simpson index on day 3, at 1 month, 6 months and 1 year were 1.117, 1.460, 2.088, 2.50 and 0.443, 0.408,0.229, 0.143 respectively. Conclusions Infants' intestines harbor abounding bacterial genomes. Distinct individual differences exist in infants in terms of intestinal bacterial abundance and composition. The abundance and diversity ofgut bacteria increase over time.