Fig. 2: Within three months, preterm infant oral microbiota diversity and composition resembles full-term infants.

Using 2000 sequences per sample, alpha diversity variation decreases over time in preterm infants using both (a) observed species and (b) Faith’s phylogenetic diversity metrics. The factor that had the most significant impact was the collection time point of the preterm samples, showing the differences in composition over a short period of time (c and d). Using unweighted UniFrac metric, composition of PT1 samples was more densely populated in the bottom section of PC2 but was spread across PC1, whereas PT2 and full-term infant samples had small density peaks across PC1 but overlapped each other in PC2 (e). Adults were significantly different from infant samples over Axis 2 and 3 (f). Samples were color-coded according to the time of collection and if they were a preterm or full-term infant, or adult. Pairwise significant differences are labeled with the corresponding q value.