In vitro screening of glycan substrate specificity
We selected a variety of growth substrates representing putative glycan components of MDCF-2 plus glucose (Sigma-Aldrich, G8270) as a positive control and chondroitin sulfate (Thermo Fisher Scientific, J66156.06) as a negative control. Growth substrates included arabinan, arabinoxylan, β-glucan, galactan, galactomannan, rhamnogalacturonan, xyloglucan and xylan (all obtained from Neogen Megazyme; Supplementary Table We selected five 