Luria agar

The list of strains used in this study is given in S1 Table. S. pneumoniae D39 was grown either in brain heart infusion broth (BHI), blood agar base (Oxoid, UK) supplemented with 5% (v/v) defibrinated horse blood (Oxoid), or in Chemically Defined Medium (CDM) supplemented with 55 mM glucose or different concentrations of dialysed bovine sub-maxillary mucin (Sigma) [9 (link), 11 (link), 61 (link)]. Escherichia coli cultures were grown on Luria broth, or Luria agar (Oxoid, UK). Spectinomycin and kanamycin were added at 100- and 250 μg/mL, respectively, for pneumococcal cultures, and for E. coli ampicillin and kanamycin were used at 100- and 150 μg/mL, respectively.

The strains used in this study are listed in Table S1. S. pneumoniae D39 was grown microaerobically at 37°C either in brain heart infusion broth (BHI), blood agar base (BAB) (Oxoid, UK) supplemented with 5% (v/v) defibrinated horse blood, or in chemically defined medium (CDM) supplemented with 55 mM of the selected sugar (Yesilkaya et al., 2006 (link), 2008 (link)). For anaerobic growth, an anaerobic cabinet was used. Escherichia coli was grown in Luria broth with shaking at 37°C, or in Luria agar (Oxoid). Growth was monitored by measuring the OD600, or by determining colony counts. Growth rates (μ) were calculated through linear regressions of the plots of ln(OD600) vs. time during the exponential growth phase. Spectinomycin, tetracycline, and kanamycin were added at 100, 15, and 250 μg/mL, respectively, for pneumococcal cultures, and for E. coli ampicillin and kanamycin were used at 100 and 50 μg/mL, respectively.