SDS-PAGE analysis of proteinase K-digested whole cell lysates of KPM22-derived E. coli and S. enterica sv. Typhimurium reference strains. LPS samples were subjected to electrophoresis on a 13% polyacrylamide gel followed by silver nitrate staining. Lane 1, wild-type E. coli strain BW30270; lane 2, KPM22; lane 3, KPM50; lane 4, KPM53; lane 5, KPM56; lane 6, KPM125; lane 7, KPM123; lane 8, KPM124; lane 9, KPM122; lane 10, S. enterica sv. Typhimurium SL1102 (Re); lane 11, S. enterica sv. Typhimurium SL3769 (Rd1); lane 12, S. enterica sv. Typhimurium SL3748 (Rb3); lane 13, S. enterica sv. Typhimurium SL3750 (Rb2); lane 14, S. enterica sv. Typhimurium SL3749 (Ra).