Open AccessChemical Structure of the Core Region of Escherichia coli J‐5 Lipopolysaccharide
Author(s) -
MüllerLoennies Sven,
Holst Otto,
Brade Helmut
Publication year - 1994
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1994.t01-1-00751.x
Subject(s) - escherichia coli , lipopolysaccharide , core (optical fiber) , microbiology and biotechnology , chemistry , computational biology , biology , physics , biochemistry , immunology , gene , optics
The lipopolysaccharide of Escherichia coli J‐5 was sequentially de‐ O ‐acylated, dephosphorylated, reduced, de‐ N ‐acylated, and N ‐acetylated. The products were separated by high‐performance anion‐exchange chromatography into a nonasaccharide ( 1 ), two octasaccharides ( 2,3 ), and a heptasaccharide ( 4 ). Compositional analysis, methylation analysis, and NMR spectroscopy revealed the structures of the products as: 1234in which 1 R is l ‐α‐ d ‐Hep p ‐(1–5)‐[α‐Kdo p ‐(2–4)‐]‐α‐Kdo p ‐(2–6)‐β‐ d ‐Glc p NAc‐(1–6)‐ d ‐GlcN‐Acol, and 2 R is l ‐α‐ d ‐Hep p ‐(1–5)‐α‐Kdo p ‐(2–6)‐β‐ d ‐Glc p NAc‐(1–6)‐ d ‐GlcNAcol (LD‐Hep, l ‐glycero‐ d ‐manno‐heptose ; Kdo, 3‐deoxy‐ d ‐ manno ‐octulopyranosonic acid; GlcNAcol, 2‐acet‐amido‐2‐deoxy‐glucitol). Fast‐atom‐bombardment mass spectrometry of de‐ O ‐acylated and dephosphorylated lipopolysaccharide showed that the isolated oligosaccharides represented the complete carbohydrate moiety of the lipopolysaccharide, and indicated that the non‐reducing terminal d ‐GlcN residue in lipopolysaccharide was present as the free base.