Analytical and Bioanalytical Chemistry

, Volume 405, Issue 23, pp 7415–7426 | Cite as

Characterization of mycobacterial triacylglycerols and monomeromycolyl diacylglycerols from Mycobacterium smegmatis biofilm by electrospray ionization multiple-stage and high-resolution mass spectrometry

  • Georgiana E. Purdy
  • Sophia Pacheco
  • John Turk
  • Fong-Fu HsuEmail author
Research Paper


The storage of triacylglycerols (TAGs) is essential for non-replicating persistence relevant to survival and the re-growth of mycobacteria during their exit from non-replicating state stress conditions. However, the detailed structures of this lipid family in mycobacteria largely remain unexplored. In this contribution, we describe a multiple-stage linear ion-trap mass spectrometric approach with high resolution mass spectrometry toward direct structural analysis of the TAGs, including a novel lipid subclass previously defined as monomeromycolyl diacylglycerol (MMDAG) isolated from biofilm of Mycobacterium smegmatis, a rapidly growing, non-pathogenic mycobacterium that has been used as a tool for molecular analysis of mycobacteria. Our results demonstrate that the major isomer in each of the molecular species of TAGs and MMDAGs consists of the common structure in which Δ918:1- and 16:0-fatty acyl substituents are exclusively located at sn-1 and sn-2, respectively. Several isomers were found for most of the molecular species, and thus hundreds of structures are present in this lipid family. More importantly, this study revealed the structures of MMDAG, a novel subclass of TAG that has not been previously reported by direct mass spectrometric approaches.


Apolar lipid Triacylglycerol Mycobacteria smegmatis Meromycolyl chain Mass spectrometry 



Electrospray ionization-MS


Fatty acid


High-resolution mass spectrometry


Linear ion-trap


Monomeromycolyl diacylglycerol





This research is supported by US Public Health Service Grants P41-RR-00954, P60-DK-20579, and P30-DK56341 (mass spectrometry facility) and AI087840 (GEP). We acknowledge the technical assistance from Meei-Hua Lin and Alan Bohrer.

Supplementary material

216_2013_7179_MOESM1_ESM.pdf (276 kb)
ESM 1 (PDF 275 KB)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Georgiana E. Purdy
    • 2
  • Sophia Pacheco
    • 2
  • John Turk
    • 1
  • Fong-Fu Hsu
    • 1
    Email author
  1. 1.Mass Spectrometry Resource, Division of Endocrinology, Diabetes, Metabolism, and Lipid research, Department of Internal MedicineWashington University School of MedicineSt. LouisUSA
  2. 2.Department of Molecular Microbiology & ImmunologyOregon Health & Science UniversityPortlandUSA

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