"Core" glycolipid of enterobacteriaceae: immunofluorescent detection of antigen and antibody.

The Re chemotype mutant of Salmonella minnesota R595 has a cell-wall glycolipid composed principally of 2-keto, 3 deoxyoctonate and Lipid A, which is an antigen widely shared by Enterobacteriaceae. High-titered antiserum against this antigen can be conjugated with fluorescein isothiocyanate for direct detection of this antigen in heterologous bacteria and staining of bacteria in tissue. Alternatively, the indirect immunofluorescence technique can be used for antigen detection on bacterial surfaces and in tissues, and this method can quantitate glycolipid antibody in mammalian sera. The latter may be particularly useful in serologic studies because, although the glycolipid antigen is a surface antigen and purified extracts can be used to coat latex particles, high-titered antisera will not agglutinate bacteria or coated latex particles.