Figure 12.

In vitro synthesis of the entire S. typhimurium outer core OS. Gal-Glc-Hep₂-1-deP-KLA (labeled C) was reacted with S. typhimurium WaaI (0.1 mg/mL) for 30 min to generate Gal-[Gal]-Glc-Hep₂-1-deP-KLA (labeled D_s). Next, WaaJ (0.1 mg/mL) was added to generate Glc-Gal-[Gal]-Glc-Hep₂-1-deP-KLA (labeled E_s). S. typhimurium WaaK (0.1 mg/mL) was added in the presence or absence of 1 mM UDP-GlcNAc and incubated for the times indicated. Only in the presence of UDP-GlcNAc was the product labeled F_s formed. This product represents the in vitro formation of the entire outer core on a defined lipid acceptor.