α mycolic acid c 80

All lipid standards including PE (16:0/17:1(c9Z)), PC (16:0/17:1(c9Z)), α-mycolic acid (C-80) and E. coli total lipid extract were purchased from Avanti Polar Lipids (Alabaster, Alabama). Structures and molecular weights of cyclopropane lipid standards are shown in Table S1. Gradient grade OmniSolv water, acetonitrile (ACN) and methanol were purchased from VWR (Radnor, PA). Chloroform and Myobacterium bovis (M. bovis) lipid extract were purchased from Sigma Aldrich (St. Louis, MO). LC grade isopropyl alcohol (IPA) and Optima LC-MS grade formic acid, ammonium formate and ammonium acetate were purchased from Thermo Fisher Scientific (Waltham, MA). Mycobacterium tuberculosis strains H37rV (NR-14837), CDC1551 (NR-14838), and HN878 (NR-14839) total lipids were obtained through BEI Resources, NIAID, NIH.

EquiSPLASH™ LIPIDOMIX® Quantitative Mass Spec Internal Standard, α-mycolic acid (C80) and methoxy cis α-mycolic acid were purchased from Avanti Polar Lipids (Birmingham, AL). Optima LC-MS grade acetonitrile plus 0.1% formic acid, water plus 0.1% formic acid, methanol and 2-propanol were purchased from Fisher Chemical (Waltham, MA). LC grade chloroform was purchased from Sigma (St. Louis, MO). All other chemicals were purchased from Sigma (St. Louis, MO) and were of analytical grade quality. A 10 mM stock solution of ammonium formate at pH 6.2 was used as a standard buffer.