Occurrence of the toxin dehydroabietic acid in Salmonella typhimurium

Many strains of Salmonella typhimurium studied in our lab demonstrated mark ed differences in the pathogenicity for guinea pig, chicken and Hela cells. As a result, a pathogenic strain of S. typhimurium, strain 9SR2, was evalu ated for lipophilic components that may be associated with virulence using gas chromatography/mass spectrometry. The hydroxylated fatty acids 2-hydrox ytetradecanoic acid (2-OH-14:0) and 3-hydroxytetradecanoic acid (3-OH-14:0) often present in lipid A, a potent endotoxin, were observed as their methy l esters. The cyclic fatty acids methylene-hexadecanoic acid (C17 Delta) an d methyleneoctadecanoic acid (C19 Delta) also were detected. The nephrotoxi c and neurotoxic diterpenoid resin acid, dehydroabietic acid, was observed for the first time from S. typhimurium in both the total lipid and diglycer ide fractions and determined as its methyl ester at m/z 314.2246, Due to it s previously established toxicity, dehydroabietic acid may be a factor asso ciated with virulence of S. typhimurium. Published by Elsevier Science Ltd.