The endotoxic glycolipid of Salmonella minnesota R595 was extracted either by the phenol-water method (GL) or directly with chloroform-methanol (GL-DE). Both glycolipids were soluble in chloroform-methanol (4:1). The yield of GL-DE was higher than that of GL. Examination of both materials by thin-layer chromatography (TLC) and column chromatography demonstrated that GL and GL-DE are chromatographically similar and that both are heterogeneous. Four fractions isolated from GL-DE with preparative TLC showed equal endotoxic activities in Shwartzman skin reaction, Limulus lysate gelation activity, and chick-embryo lethality. Chemical analyses indicate that all four are glycolipid in nature. The chromatographic behavior and the similar molar ratios of chemical constituents in these four components suggest that they may be chromatographically different due to polymerism. More detailed studies of some biological parameters have been done with GL and GL-DE by comparison with an endotoxin obtained from a smooth strain of Serratia marcescens. It was found that glycolipid showed activities similar to or higher than those observed for endotoxin.
|Original language||English (US)|
|Journal||Journal of Infectious Diseases|
|State||Published - Jul 1973|
Bibliographical noteFunding Information:
This research was supported by grants no. AI-05581 and HL-01601 from the U.S. Public Health Service and by a grant from the New York Cancer Research Institute.