New types of liposidomycins produced by Streptomyces that inhibit bacterial peptidoglycan synthesis - Structure elucidation of fatty acid components by tandem mass spectrometry

The structures of the fatty acid components of various new liposidomycins w ere determined using tandem mass spectrometry; the negative FAB/MS/MS/MS te chnique for liposidomycins with a 3-methylglutaric acid moiety and the nega tive FAB/MS/MS technique for liposidomycins without a 3-methylglutaric acid moiey. This structural information was obtained by analysis of peaks due t o charge-remote fragmentations for 3-hydroxycarboxylate anions or carboxyla te anions which were generated from liposidomycin molecules in a mass spect rometer. The MS/MS/MS technique that can exclude the matrix-derived and/or interfering ions showed higher sensitivity than the MS/MS technique.