Fig. S3.

Fatty acid profiles of Mabs R and ΔMAB_4780 strains. Total fatty acids from washed and dried mycobacterial pellets were saponified and carboxymethylated in 0.5 M methanolic HCl at 80 °C overnight. Fatty acid methyl esters (FAMEs) were extracted with chloroform, dried, and analyzed by GC–MS. Representative total ion chromatograms of total FAMEs from (A) Mabs R and (B) ΔMAB_4780 strains, showing a family of compounds ranging from C14:0 to C24:0, with a major signal identified as C16:0. The structure of all compounds was assigned based on retention time of standard molecules and individual electronic impact fragmentation patterns. Comparison of the FAME patterns did not show important variations, except for a reduction of the C18:0 ratio in ΔMAB_4780.