Extended Data Fig. 6: Mass spectrometry confirms LytH-ActH amidase activity.

a, Glycan strands were made from native Lipid II using SgtB^WT protein and treated with the LytH complex prior to LC-MS analysis. In the presence of LytH^WT-ActH, the tetrasaccharide-monopeptide was observed, but only the monomer (starting material) was observed in the LytH^D195A-ActH reaction. We could not detect the released stem peptide in these reactions with native glycan strands likely due to the poor ionization efficiency of the released pentaglycine-containing stem peptide. b, The chemical structure and isotope distributions for the disaccharide peptide species (blue peak) shown in Fig. 2f. c, The chemical structure and isotope distributions for the synthetic stem peptide product (red peak) shown in Fig. 2f.