title: Nature and linkage type of fatty acids present in lipopolysaccharides of phase I and II Coxiella burnetii.
abstract: The constituent fatty acids of lipopolysaccharides (LPS) of Coxiella burnetii (phase I and II) were qualitatively and quantitatively analysed by combined gas-liquid chromatography/mass spectrometry. The total fatty acid content (per mg LPS) was determined as 90.0 nmol (2.3 wt%) for LPS of phase I cells (LPS I) and 179.1 nmol (4.8 wt%) for LPS of phase II cells (LPS II). Of the 24 different acyl residues characterized (12 to 18 carbon atoms), nine were 3-hydroxy fatty acids (normal, iso- and anteiso-branched) which quantitatively predominated. All 3-hydroxylated fatty acids were found to possess the (R)-configuration, to be exclusively amide-linked and to be acylated at their 3-hydroxyl group. Ester-linked nonhydroxylated fatty acids (normal, iso- and anteiso-branched) were present but ester-bound 3-hydroxy- or 3-acyloxyacyl residues were lacking from C. burnetii LPS I and LPS II. As the major acyl group (R)-3-(12-methyl-tetradecanoyloxy)-12-methyl-tetradecanoic acid was identified. Our results show that the complex fatty acid spectrum of C. burnetii differs considerably from that of LPS of other Gram-negative bacteria. They further suggest an enormous heterogeneity of the lipid A component of C. burnetii LPS I and LPS II.
mesh_terms: D002849:Chromatography, Gas; D003381:Coxiella / Q000032:analysis* / Q000502:physiology; D005227:Fatty Acids / Q000032:analysis*; D008050:Lipid A / Q000032:analysis; D008070:Lipopolysaccharides / Q000032:analysis*; D013058:Mass Spectrometry
chemical_list: D005227:Fatty Acids; D008050:Lipid A; D008070:Lipopolysaccharides