Molecular recognition in the LysM/Carbohydrate system

Molecular recognition of carbohydrates regulates many essential biological processes in living organisms. One carbohydrate binding module (CBM) conserved across all kingdoms is LysM: which is present in bacterial extra-cellular proteins including hydrolases, adhesins and virulence factors such as Protein A from Staphylococcus aureus. LysM modules consist of 43–50 amino acids that adopt a highly conserved beta-alpha-alpha-beta fold, with particularly high sequence conservation in the first 16 residues1,28,17. Prokaryotic LysM modules bind peptidoglycan, the main component of the bacterial cell wall, made of alternating N-acetylglucosamine (GlcNAc) and Nacetylmuramic acid (MurNAc) residues, substituted by short peptide stems