Structure of E. coli C's rough type LPS. The rough type LPS of E. coli C is composed of two parts: lipid A (composed of an acetylated and 1,4′-diphosporylated β(1→6)-linked glucosamine (GlcN) disaccharide) and the core OS (Raetz and Whitfield 2002). The core OS is subdivided into a structurally conserved inner core and an outer core. The dashed lines show nonstoichiometric substitutions of phosphate (P), ethanolamine (EtNP), and 3-deoxy-d-manno-octulosonic acid (Kdo) residues on the LPS (Kojima et al. 2010). Details of the LPS assembly process are provided in supplementary figure S1, Supplementary Material online.