Structure of the lipopolysaccharide from an Escherichia coli heptose-less mutant. I. Chemical degradations and identification of products.

摘要: The structure of lipopolysaccharide from a heptose-less mutant Escherichia coli K-12 has been investigated. Lipopolysaccharide isolated 32P-labeled cells was treated with mild alkali to yield two separable components: [OH-LPS]-I (approximately 70%) and [OH-LPS]-II 30%). Mild acidic treatment gave mainly product which identified as (4-O-phosphoryl-N-beta-hydroxymyristyl-D-glucosaminyl)-beta(1 leads 6)-N-beta-hydroxymyristyl-D-glucosamine 1-phosphate (Compound I). Further hydrolysis both yielded the main II). structures above products were deduced by combination compositional analyses, sensitivity phosphomonoesterase, rates phosphate groups alkali-catalyzed beta elimination residues following appropriate oxidation hydroxyl groups. These studies together work reported in accompanying papers have led identification species E. strain contain single glucosamine dissacharide unit but differ having monosubstituted or pyrophosphate at glycosidic position. Each also appeared be heterogeneous respect number esterified fatty acyl