FIGURE 5.
Charge-deconvoluted ESI FT-ICR mass spectra in negative ion mode showing the O-deacylated lipid A sample from A. pyrophilus (LAtetrainset structure; 1651.12 u (20)). The lipid A molecule (91 μm) was used as an acceptor in reactions containing 100 mm HEPES, pH 7.5, 10% glycerol, 10 mm MgCl2, 2 mm Kdo, 5 mm CTP, and 3.2 mm Triton X-100. The mixtures were incubated at 60 °C for 1 h with no enzymes (A) and in the presence of 17 milliunits of purified KdsBAAE and 75 μm purified WaaAAAE (B). Peaks presumably representing molecules with variations in acyl chain length are labeled with an asterisk.