Figure 2.

LPS structures in 12 Asian H. pylori strains. LPS structures in 4 Chinese strains (F-58C, R-58A, F-15A, and R-7A), 3 Singaporean strains (H-607, H-507, and H-428), and 5 Japanese strains (CA2, CA4, CA5, GU2, and CA6) [8]. * All these strains are assumed to have the same conserved core-Trio structures. ∆ means the structure is absent. The heptan is completely absent in the LPS structures of all 12 Asian strains, which is accompanied by the simultaneous absence of the glucan (with CA6 LPS as an exception, it has a glucan composed of two Glc residues). However, for strain R-58A, LPS in all the Asian strains have simultaneous expression of type 1 and type 2 Lewis chains. Strikingly, the type 1 Lewis chain (Gal-β-(1,3)-GlcNAc) can serve as a capping structure connected to type 2 chain (Gal-β-(1,4)-GlcNAc) in a single LPS molecule. For example, the LPS molecule in strains H-507, H-428, and CA2 is capped by a type 1 Le^b connected to polymeric type 2 Le^x chain. + indicates the Lewis antigen attachment point to the core-Trio structures.