TABLE 2.

Composition of monomethyl branched unsaturated fatty acids from methyl ester fraction V of argentation-TLC from wild-type M. tuberculosis H37Rv (missing in the msl5 mutant)

Fatty acidaRelative amt in methyl ester fraction V (%)bDiagnostic ions used for identificationc
2-Me C16:11655, 88, 101, 250, 282
2-Me C17:1755, 88, 101, 264, 296
2-Me C18:1355, 88, 101, 278, 310
2-Me C18:25855, 88, 101, 127, 277, 308
2-Me C19:1455, 88, 101, 292, 324
2-Me C19:2355, 88, 101, 127, 291, 322
2-Me C20:1255, 88, 101, 306, 338
2-Me C20:2755, 88, 101, 127, 304, 338
  • a Identified by GC-MS by their number of carbon atoms and double bond. Me, methyl.

  • b Fraction V was derived from argentation-TLC of total fatty acid methyl ester from the wild type (Fig. 2A).

  • c The ion at m/e 88 was much weaker than that observed with 2-methyl branched acids without a double bond at position C-2.