FIG. 1.

LPS structure of V. cholerae. (A) LPS core oligosaccharide backbone proposed for V. cholerae O1 and O139. The representation is based on the structural analysis of Knirel et al. (33) and Vinogradov et al. (64), indicating a conserved core oligosaccharide for both serogroups. The site of the attachment of the O1 antigen has not been determined. The O139 antigen was found to be attached to the HepIII residue. Hep, l-glycero-d-manno-heptose; Kdo, 3-deoxy-d-manno-octulosonic acid; PEtn, 2-aminoethyl phosphate. (B) Analysis of LPS by SDS-PAGE and Silver staining. Lanes: 1, P27459res29/pACYC177; 2, P27459res29/pACYCgalU; 3, P27459galU; 4, P27459ΔgalE::cm; wt, P27459.