Eine neue Gruppe von Salmonella R‐Mutanten

作者：H. J. Risse, Wulf Dröge, Ellen Ruschmann, Otto Luderitz, Otto Westphal, J Schlosshardt · 发表于：European Journal of Biochemistry · 年份：1967 · DOI：10.1111/j.1432-1033.1967.tb00066.x · 被引用次数：33 · 研究领域：Antibiotic Resistance in Bacteria、Escherichia coli research studies、Salmonella and Campylobacter epidemiology

From the wild types (S forms) of Salmonella minnesota and Salmonella ruiru R mutants (R forms) were isolated which produce hexose‐less cell wall lipopolysaccharides of chemotype Rd. These lipopolysaccharides are composed of lipid A (glucosamine, long‐chain fatty acids, phosphoric acid), 2‐keto‐3‐deoxy‐octonate (KDO), and l‐glycero‐d‐manno‐heptose (heptose), while those of the parent S forms contain additional galactosamine, glucosamine, galactose and glucose. R mutants with lipopolysaccharides of chemotype Rd could be differentiated into two groups, Rd1 and Rd2. Group Rd1 comprises the S. minnesota mutants mR7 and mRz. Their lipopolysaccharides contain about 14% heptose. Partial hydrolysis of the mR7 lipopolysaccharide resulted in the formation of three main split products: lipid A, mR7A and mR7B. mR7A was identified as free 2‐keto‐3‐deoxy‐octonate, while mR7B was composed of heptose and 2‐keto‐3‐deoxy‐octonate. Depending on the method applied for the estimation of 2‐keto‐3‐deoxy‐octonate, the molar ratio of heptose/2‐keto‐3‐deoxy‐octonate was found to be 2:0.3 (on the basis of the thiobarbituric acid reaction) or 2:1 (according to the semicarbazide reaction). When permethylated mR7B was methanolyzed and the products analyzed by gas chromatography, two peaks (7.4 and 15.0 min) were observed. The 7.4 min peak was identical with one of the two peaks (7.4 and 9.6 min) obtained with permethylated authentic d‐glycero‐l‐manno‐heptose, the optical antipode of the bacterial heptose. ...