title: Structure and molecular species composition of three homologous series of alpha-mycolic acids from Mycobacterium spp.
abstract: Three homologous series of alpha-mycolic acids (dicyclopropanoyl acids, monocyclopropanoyl monoenoic acids and dienoic acids) from 16 rapidly growing and 14 slowly growing mycobacteria were separated by argentation thin-layer chromatography and analysed by gas chromatography/mass spectrometry of their trimethylsilyl ether derivatives. Mycobacterial species were separated into five groups. Strains of group A contained similar amounts of even and odd carbon-numbered dienoic acids, with a methyl branch on the odd acids and a C24-alpha-unit, as typified by Mycobacterium fortuitum and M. chitae. Group B strains possessed similar amounts of even carbon-numbered dicyclopropanoyl alpha-mycolic acids and odd carbon-numbered unsaturated acids with C22- and C24-alpha-units, as found in M. phlei and M. diernhoferi. Group C strains contained mainly even carbon-numbered dicyclopropanoyl acids with C22- and C24-alpha-units, as shown by M. vaccae and M. aurum. Group D strains possessed mainly odd carbon-numbered dienoic acids with a methyl branch and a C24-alpha-unit, as seen in M. triviale and M. nonchromogenicum. Group E strains had mainly even carbon-numbered dicyclopropanoyl acids with C24- or C26-alpha-units, as found in M. avium and M. tuberculosis. Many rapidly growing mycobacteria also produced alpha'-mycolic acids which were shorter in the length of the main carbon chain but whose alpha-units were the same as those in alpha-mycolic acids from the same species. These alpha'-mycolic acids had either one or two double bonds and showed variations in both their unsaturation and overall size, which may be useful in taxonomic studies.
authors.affiliation: Department of Bacteriology, Niigata University School of Medicine, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Kaneda
authors.forename: S
authors.initials: S
authors.lastname: Imaizumi
authors.forename: S
authors.initials: S
authors.lastname: Mizuno
authors.forename: T
authors.initials: T
authors.lastname: Baba
authors.forename: M
authors.initials: M
authors.lastname: Tsukamura
authors.forename: I
authors.initials: I
authors.lastname: Yano
mesh_terms: D002264:Carboxylic Acids; D055598:Chemical Phenomena; D002621:Chemistry; D002855:Chromatography, Thin Layer; D003521:Cyclopropanes; D003998:Dicarboxylic Acids; D008401:Gas Chromatography-Mass Spectrometry; D006865:Hydrogenation; D009161:Mycobacterium / Q000378:metabolism*; D009169:Mycobacterium tuberculosis / Q000378:metabolism; D009171:Mycolic Acids; D009170:Nontuberculous Mycobacteria / Q000378:metabolism
chemical_list: D002264:Carboxylic Acids; D003521:Cyclopropanes; D003998:Dicarboxylic Acids; D009171:Mycolic Acids