Figure 3
From: Detoxifying Escherichia coli for endotoxin-free production of recombinant proteins
Charge deconvoluted ESI FT-ICR mass spectra in negative ion mode of LPS isolated from BL21 (DE3)-derived mutants. Mass numbers given refer to the monoisotopic masses of neutral molecules. Peaks representing molecules with variations in acyl chain length are labeled with asterisks (∆m = 14.02 u). The mass spectra depict the progress in elimination of lipid IVA heterogeneity by sequential deletion of genes encoding the addition of acyl chains and P-EtN to the lipid A precursor.