Abstract
The lipopolysaccharides (LPS) of Chlamydia trachomatis, Acinetobacter calcoaceticus var. anitratus, and Re mutants of Salmonella sp. were shown to share related immunodeterminants , as demonstrated by double immunodiffusion and immunoblotting from sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels. The cross-reactive material in the extracellular slime of A. calcoaceticus var. anitratus was shown to be released LPS. The Acinetobacter LPS was found to separate in sodium dodecyl sulfate-polyacrylamide gel electrophoresis into three fractions. The cross-reactive component was the fraction migrating fastest, at a rate identical to Re-type LPS of Salmonella sp. The Acinetobacter LPS could be used as antigen in complement fixation assays performed on paired sera of patients with chlamydial pneumonia; it gave results identical to those of the chlamydial complement fixation glycolipid antigen conventionally used in such assays in 9 of 10 patients.