Fig. 3. Enteric pathogen growth in pure culture and relative abundances in fecal communities grown on glycans.

Six strains of a Klebsiella pneumoniae, b Escherichia coli, or c Enterococcus faecium were cultured with 5 g l⁻¹ of a single SG (n = 148) or reference glycan (n = 32) in CM3 medium. Data is the mean maximum growth (OD₆₀₀) of triplicate cultures; strain names are shown above each plot. Fecal communities from a healthy donor were OD₆₀₀-normalized to contain 8% of d K. pneumoniae CDC 003, e E. coli CDC 001, or f E. faecium ATCC 700221 and cultured in triplicate with 5 g l⁻¹ of an SG (n = 45) or reference glycan (n = 17) for 45 h in MM29 medium. The relative abundances of the pathogens were quantified by 16S rRNA gene sequencing. Data points show FOS (indigo circle), BRF (yellow circle), or BQM (orange triangle) cultures. Box plots show median and interquartile ranges. Asterisks show significance (*p < 0.05, **p < 0.01) by two-sided Wilcoxon rank-sum test. Source data are provided as a Source Data file. SGs Synthetic Glycans, OD₆₀₀ optical density at 600 nm, FOS fructo-oligosaccharides.