Molecular organization of the outer membrane of Salmonella typhimurium. Different release of lipopolysaccharide from wild type and lipopolysaccharide mutant cells by EDTA treatment.

Cells of Salmonella typhimurium wild type and of several well defined lipopolysaccharide mutants were treated with EDTA. The percentage release of lipopolysaccharide and phospholipid was determined. The results obtained show that the release of lipopolysaccharide by EDTA declines along with the gradually diminishing chain length of the lipopolysaccharide, although the total amount of lipopolysaccharide, although the total amount of lipopolysaccharide was found to increase at the same time in the respective mutants. Implications of these findings for the organization of the outer membrane are discussed.