title: Lipids of antibiotic-resistant and -susceptible members of the Enterobacteriaceae.
abstract: Lipids of antibiotic-resistant and related -susceptible strains of the Enterobacteriaceae were extracted with chloroform-methanol and characterized by thin-layer chromatography, densitometry, and fatty acid analysis using gas chromatography. Quantitative differences which correlated with antibiotic resistance existed among the phospholipids and fatty acids. A relatively higher concentration of a ninhydrin-positive phospholipid concentration with a lower amount of phosphatidylethanolamine was observed in antibiotic-resistant strains of serratia marcescens. Bacterial strains which harbored R-factor 222 had a higher ratio of phosphatidylglycerol to diphosphatidylglycerol than their respective parent strains while those strains which were resistant to the polymyxins had a lower ratio of these phospholipids. Differences in the relative amounts of certain unsaturated and cyclopropane fatty acids were observed between susceptible and resistant strains. Such differences, however, were dependent upon a particular genus and species.
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000032:analysis* / Q000187:drug effects; D005227:Fatty Acids / Q000032:analysis; D008055:Lipids / Q000032:analysis*; D010743:Phospholipids / Q000032:analysis; D011513:Proteus mirabilis / Q000032:analysis* / Q000187:drug effects; D011815:R Factors; D012706:Serratia marcescens / Q000032:analysis* / Q000187:drug effects; D013045:Species Specificity
chemical_list: D000900:Anti-Bacterial Agents; D005227:Fatty Acids; D008055:Lipids; D010743:Phospholipids