Isolation of a mutant from Salmonella typhimurium producing acyl-deficient lipopolysaccharides.
The present paper describes the isolation and characterization of a mutant (mutant Ts7) of Salmonella typhimurium that is conditionally defective in the incorporation of dodecanoic and tetradecanoic acid into lipopolysaccharide precursor structures. Enrichment of mutant Ts7 was achieved by free-flow electrophoresis and was based on a previous observation that at least some Salmonella mutants conditionally blocked in the synthesis of the 3-deoxy-D-manno-octulosonic acid (dOc1A)-lipid-A region exhibit higher electrophoretic mobilities than cells with intact dOc1A-lipid-A regions. Under nonpermissive conditions (42 degrees C) mutant Ts7 accumulates at least two incomplete dOc1A-lipid-A structures. One is made up of glucosamine, phosphate, dOc1A, and 3-hydroxytetradecanoic acid in a molar ratio 1.0:1.3:1.0:2.2 and is devoid of dodecanoic and tetradecanoic acid. The other structure has the same basic structure but contains hexadecanoic acid.
Lehmann
V
V
Deutsches Krebsforschungszentrum Heidelberg, Institut für Immunologie und Genetik, Federal Republic of Germany.
Benninghoff
B
B
D000107:Acetylation; D002848:Chromatography, DEAE-Cellulose; D002854:Chromatography, Paper; D004586:Electrophoresis / Q000379:methods; D006017:Glycolipids / Q000096:biosynthesis / Q000235:genetics; D007850:Lauric Acids / Q000378:metabolism; D008050:Lipid A / Q000096:biosynthesis; D008070:Lipopolysaccharides / Q000235:genetics*; D009154:Mutation; D019814:Myristic Acid; D009227:Myristic Acids / Q000378:metabolism; D012486:Salmonella typhimurium / Q000235:genetics* / Q000378:metabolism
D006017:Glycolipids; D007850:Lauric Acids; D008050:Lipid A; D008070:Lipopolysaccharides; D009227:Myristic Acids; D019814:Myristic Acid; C030358:lauric acid