Colicin export was studied in different Salmonella typhimurium strains lacking the O-antigen repeating units (O-) and different strains with different chemotypes for the lipopolysaccharide core, as well as the wild-type strain (O+), to determine the role of lipopolysaccharide length on colicin E1 export. While the lipopolysaccharide length influences the levels of external hemolytic activity in S. typhimurium, no effect was detected on colicin E1 export.