Fig. 3
A. FTICR-MS of lipopeptides produced by B. subtilis. (A) B. subtilis PB2-L1, (B) B. subtilis LS1, (C) B. subtilis LS6 and (D) B. subtilis LS9. The values 1008.7, 1022.7 and 1036.7 correspond to the calculated H+ adducts of surfactin A (A) with a fatty acid residue ranging from 13 to 15 carbon atoms. The values 909.6, 923.6 and 937.6 correspond to the calculated H+ adducts of [∆Leu3]surfactin (B) with fatty acid bodies ranging from 14 to 16 carbon atoms. The values 907.6, 921.7 and 935.7 correspond to the calculated H+ adducts of [∆Asp5]surfactin (C) with fatty acid bodies ranging from 14 to 16 carbon atoms. The [∆Leu6]surfactin values (D) are the same as the [∆Leu3]surfactin values (B). The (b, c, d) shows FTICR-MS/MS of [∆Leu3]surfactin, [∆Asp5]surfactin, [∆Leu6]surfactin. B. The proposed structure of engineered Surfactin A produced by B. subtilis