Structures of cell-wall glycopolymers of Lactococcus lactis BIM B-1024

Glycopolymers of two types were isolated from the cell wall of Lactococcus lactis BIM B-1024 by stepwise extraction with cold and hot 10% CCl₃CO₂H and separated by anion-exchange gel chromatography. The following structures of the glycopolymers were established by sugar analysis, dephosphorylation with 48% HF, 1D and 2D NMR spectroscopy, and ESI-MS:

β-D-Galp-(1→4)-β-D-Glcp-(1→6)┐

→4)-β-D-Galp-(1→4)-β-D-Glcp-(1→4)-α-D-Glcp-(1→ PSI

β-D-Glcp-(1→3)┐

→60-α-D-GalpNAc-(1→3)-β-D-GalpNAc-(1→5)-Rib-ol-1-P-(O→ PSII

β-D-Glcp-(1→4)┘

Polysaccharides with the same or similar structures to PSI have been found earlier in various Lactobacillus species, whereas, to our knowledge, the structure of PSII is new.