Fig. 1
Infant microbiota composition in preterm gut driven by diet and birth weight. Principal component analysis (PCA) of 199 samples from the 30 infants over the first 60 days based on Bray-Curtis distances between samples [2000 reads/sample]. Scatterplots are colored based on the following: a nutritional exposures on a sample-by-sample basis [MBM maternal breast milk, DM pasteurized human donor milk, IF infant formula, NPO nil per os, nothing by mouth]; b birth weight class [VLBW very low birth weight infants 1000–1500 g, ELBW extremely low birth weight infants <1000 g]; and c week of life [shades of yellow—“early” samples <3 weeks; shades of blue—“late” samples after 3 weeks]. Early samples cluster together regardless of nutritional exposures. Closer proximity of samples (points) equals more similar microbiota composition. Separation of samples within each category is significant [FDR-adjusted PERMANOVA p < 0.001], and R 2 values are noted