Structural elucidation of the extracellular and cell-wall teichoic acids of Staphylococcus aureus MN8m, a biofilm forming strain.

Extracellular teichoic acid, an essential constituent of the biofilm produced by Staphylococcus epidermidis strain RP62A, is also an important constituent of the extracellular matrix of another biofilm producing strain, Staphylococcus aureus MN8m. The structure of the extracellular and cell wall teichoic acids of the latter strain was studied by NMR spectroscopy and capillary electrophoresis-mass spectrometry. Both teichoic acids were found to be a mixture of two polymers, a (1-->5)-linked poly(ribitol phosphate), substituted at the 4-position of ribitol residues with beta-GlcNAc, and a (1-->3)-linked poly(glycerol phosphate), partially substituted with the D-Ala at 2-position of glycerol residue. Such mixture is unusual for S. aureus.