Extended Data Fig. 3: Reaction mechanism of GglsA.
From: Biosurfactant biosynthesis by Alcanivorax borkumensis and its role in oil biodegradation
a, The GglsA protein carrying the Ser1177Ala mutation to disable thioesterase activity was expressed in E. coli. Glycine-glucolipid intermediates bound to the phosphopantetheine group were released with cysteamine and analyzed by LC-MS. The MS/MS spectrum of the peak eluting at 48.3 min (inset) shows the fragmentation of the proton adduct of the di-cysteamine derivative of the aglycone H(O-10:0)4Gly carrying four acyl groups. b, The GglsA construct containing the C-A-T domains but lacking the TE domain was expressed in E. coli. The aglycones produced were released by cysteamine cleavage. LC-MS analysis revealed the synthesis of four different aglycones with four, three, two or one 3-hydroxydecanoyl groups with different retention times and MS/MS spectra. The insets show the LC-MS chromatograms for the parental ions (x axis, time in min).
