Archaeal Phospholipid Biosynthetic Pathway Reconstructed in Escherichia coli
Figure 3
Radio-TLC and LC/ESI-MS analyses of the archaeal-type lipids synthesized in E. coli. (a) Crude extract from E. coli harboring pBAD-ALB4 was incubated with FPP, [14C]IPP, and DHAP. Reversed-phase radio-TLC analysis of the products was performed after dephosphorylation. S.F., solvent front; Ori., origin. (b) LC profiles of lipids extracted from E. coli harboring pBAD-ALB4 (lower) or its parent plasmid, pBAD18 (upper). (c) Positive ESI-MS ion spectrum of a peak in (b) around 22 min. (d) and (e) MS/MS analyses of the ions in (c), with m/z of 659.6 and 835.6, respectively. (f) Positive ESI-MS ion spectrum of the LC peak corresponding with that analyzed in (c). Exclusively for this analysis, the elution buffer was changed from sodium based to potassium based. (g) Negative ESI-MS ion spectrum of a peak in (b) around 22 min. (h) MS/MS analysis of the ion in (g), with an m/z of 789.5.
