Rapid identification of bacteria by direct matrix-assisted laser desorption/ionization mass spectrometric analysis of whole cells

Rapid Commun Mass Spectrom. 1996;10(15):1992-6. doi: 10.1002/(SICI)1097-0231(199612)10:15<1992::AID-RCM789>3.0.CO;2-V.


Several characteristic ions were observed during the direct analysis of a variety of both gram-negative and gram-positive intact bacterial cells by the matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) technique. The entire process, involving absolutely no sample processing, could be completed in less than ten minutes. A number of specific biomarkers, generated reproducibly for each type of cell from the corresponding mass spectrum, permitted the identification, as well as the distinction, of pathogenic bacteria from their non-pathogenic counterparts. In addition, individual strains of a specific organism could also be differentiated easily. Some of these biomarkers correspond to those observed earlier during the MALDI-MS analysis of protein extracts of the same bacteria. This approach, which can yield valuable data for rapid classification and detection of microorganisms, represents a substantial breakthrough for rapid screening of environmental as well as biological samples.

MeSH terms

  • Bacteria / chemistry*
  • Bacteria / classification*
  • Bacterial Proteins / chemistry
  • Biomarkers
  • Species Specificity
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization


  • Bacterial Proteins
  • Biomarkers