Science China Life Sciences

, Volume 54, Issue 1, pp 48–53 | Cite as

Whole-cell matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for rapid identification of bacteria cultured in liquid media

Open Access
Special Topic Research Papers

Abstract

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been used for many years to rapidly identify whole bacteria. However, no consistent methodology exists for the rapid identification of bacteria cultured in liquid media. Thus, in this study we explored the use of MALDI-TOF MS analysis for rapid identification of cells cultured in liquid media. We determined that 2,5-dihydroxybenzoic acid (50 mg mL−1, 50% acetonitrile, 0.1% trifluoroacetic acid) was the best matrix solution for MALDI-TOF MS for this type of study. Moreover, the tested strains were successfully differentiated by principal component analysis, and the main characteristics of the mass peaks for each species were found in mixed culture samples. In addition, we found that the minimum number of cells for detection was 1.8×103. In conclusion, our findings suggest that MS-based techniques can be developed as an auxiliary method for rapidly and accurately identifying bacteria cultured in liquid media.

Keywords

MALDI-TOF MS bacteria PCA identification 

References

  1. 1.
    Somtcjemko V, Iredell J R, Gilbert G L. Pathogen profiling for disease management and surveillance. Nat Rev Microbiol, 2007, 5: 464–470, 10.1038/nrmicro1656CrossRefGoogle Scholar
  2. 2.
    Widjojoatmodjo M N, Fluit A C, Verhoef J. Rapid identification of bacteria by PCR-single-strand conformation polymorphism. Clin Microbiol, 1994, 32: 3002–3007, 1:CAS:528:DyaK2MXivFWnu78%3DGoogle Scholar
  3. 3.
    Pershing D H, Tenover F C, Versalovic J, et al. Molecular microbiology: Diagnostic principles and practice, 8th ed. Washington DC: American Society for Microbiology Press, 2003Google Scholar
  4. 4.
    Anhalt J P, Fenselau C. Identification of bacteria using mass spectrometry. Anal Chem, 1975, 47: 219–225, 1:CAS:528:DyaE2MXot1CrsA%3D%3D, 10.1021/ac60352a007CrossRefGoogle Scholar
  5. 5.
    Ryzhov V, Fenselau C. Characterization of the protein subset desorbed by MALDI from whole bacterial cells. Anal Chem, 2001, 73: 746–750, 1:CAS:528:DC%2BD3MXkt1KitA%3D%3D, 10.1021/ac0008791, 11248887PubMedCrossRefGoogle Scholar
  6. 6.
    Demirev P A, Ramirez J, Fenselau C. Tandem mass spectrometry of intact proteins for characterization of biomarkers from Bacillus cereus T spores. Anal Chem, 2001, 73: 5725–5731, 1:CAS:528:DC%2BD3MXnslOhs78%3D, 10.1021/ac010672n, 11774913PubMedCrossRefGoogle Scholar
  7. 7.
    Warscheid B, Fenselau C. A targeted proteomics approach to the rapid identification of bacterial cell mixtures by matrix-assisted laser desorption/ionization mass spectrometry. Proteomics, 2004, 4: 2877–2892, 1:CAS:528:DC%2BD2cXovVynsbw%3D, 10.1002/pmic.200400911, 15378756PubMedCrossRefGoogle Scholar
  8. 8.
    Pribil P A, Patton E, Black G, et al. Rapid characterization of Bacil lus spores targeting species-unique peptides produced with an atmospheric pressure matrix-assisted laser desorption/ionization source. J Mass Spectrom, 2005, 40: 464–474, 1:CAS:528:DC%2BD2MXktFKjtbk%3D, 10.1002/jms.816, 15712356PubMedCrossRefGoogle Scholar
  9. 9.
    Sauer S, Freiwald A, Maier T, et al. Classification and identification of bacteria by mass spectrometry and computational analysis. PLoS One, 2008, 3: e2843, 10.1371/journal.pone.0002843, 18665227PubMedPubMedCentralCrossRefGoogle Scholar
  10. 10.
    Carbonnelle E, Beretti J L, Cottyn S, et al. Rapid identification of Staphylococci isolated in clinical microbiology laboratories by matrix-assisted laser desorption ionization-time of flight mass spectrometry. J Clin Microbiol, 2007, 45: 2156–2161, 1:CAS:528:DC%2BD2sXptFGltr4%3D, 10.1128/JCM.02405-06, 17507519PubMedPubMedCentralCrossRefGoogle Scholar
  11. 11.
    Mellmann A, Cloud J, Maier T, et al. Evaluation of matrix-assisted laser desorption ionization-time-of-flight mass spectrometry in comparison to 16S rRNA gene sequencing for species identification of nonfermenting bacteria. J Clin Microbiol, 2008, 46: 1946–1954, 1:CAS:528:DC%2BD1cXotFGhs7c%3D, 10.1128/JCM.00157-08, 18400920PubMedPubMedCentralCrossRefGoogle Scholar
  12. 12.
    Piseth S, Michel D, Frederique G, et al. Ongoing revolution in bacteriology: Routine identification of bacteria by Matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Clin Infect Dis, 2009, 49: 543–551, 10.1086/600885CrossRefGoogle Scholar
  13. 13.
    Torsten S. Whole-cell matrix-assisted laser desorption/ionization mass spectrometry for rapid identification of bacteriocin/lantibiotic-producing bacteria. Rapid Commun Mass Spectrom, 2008, 22: 1146–1152, 10.1002/rcm.3481CrossRefGoogle Scholar
  14. 14.
    Hoben H J, Somasegaran P. Comparison of the pour, spread and drop plate methods for enumeration of Rhizobium spp. in inoculants made from presterilized peat. Appl Environ Microbial, 1982, 44: 1246–1247, 1:STN:280:DC%2BC3crnvFKltg%3D%3DGoogle Scholar
  15. 15.
    Song Y S, Talaty N, Tao W A, et al. Rapid ambient mass spectrometric profiling of intact, untreated bacteria using desorption electrospray ionization. Chem Commun, 2007, 1: 61–63, 10.1039/b615724fCrossRefGoogle Scholar
  16. 16.
    Lindon J C, Holmes E, Nicholson J K. Metabonomics techniques and applications to pharmaceutical research & development. Pharm Res, 2006, 23: 1075–1088, 1:CAS:528:DC%2BD28XmtFCnsL0%3D, 10.1007/s11095-006-0025-z, 16715371PubMedCrossRefGoogle Scholar
  17. 17.
    Hsieh S Y, Tseng C L, Lee Y S, et al. Highly efficient classification and identification of human pathogenic bacteria by MALDI-TOF MS. Mol Cell Proteomics, 2008, 7: 448–456, 1:CAS:528:DC%2BD1cXitlylt70%3D, 18045801PubMedCrossRefGoogle Scholar

Copyright information

© The Author(s) 2011

This article is published under license to BioMed Central Ltd. Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

Authors and Affiliations

  1. 1.Pharmaceutical Department of Jilin UniversityChangchunChina
  2. 2.National Center of Biomedical AnalysisBeijingChina

Personalised recommendations