Contact

Dr. med.
Martin Christner
  • Senior physician
  • Research fellow
  • Medical specialist in Microbiology, Virology and Infectious Disease Epidemiology
Phone
+49 (0) 40 7410 - 53143
E-mail
m.christner@uke.de
Further information
MALDI-TOF typing
MALDI-TOF typing
MALDI-TOF MS
MALDI-TOF MS

MALDI-TOF mass spectrometry

MALDI-TOF mass spectrometry fingerprinting has replaced biochemical profiling as method of choice for the identification of microbial pathogens in many clinical microbiology laboratories. The technique offers high discriminatory power, short turnaround times and low costs per analysis. Currently available commercial systems provide reliable species level identification within most genera from minute amounts of solid agar culture colony material. Our research is focused on improving the technique's phylogenetic resolution and find alternative applications in microbiological testing.

Project MALDI-TOF typing

Conventional nucleic acid based typing strategies of sufficient discriminatory power are too expensive and time consuming for everyday application. Offering short turnaround time and low costs per analysis, MALDI-TOF mass spectrometry could thus be a valuable addition to existing typing tools provided that the technique's phylogenetic resolution is sufficient for routine epidemiological tasks. The aim of our studies is to investigate intraspecies spectral variability and to develop mass spectrometry based typing strategies suitable for routine clinical use.

Escherichia coli

Resources

Whole cell MALDI-TOF mass spectra from Christner et al., "Rapid MALDI-TOF mass spectrometry strain typing during a large outbreak of Shiga-Toxigenic Escherichia coli" (in revision).

Spectra acquired after sample preparation by direct depostion:
  • dsd_norec [zip, 150 MB] (triplicate spectra from 190 non-outbreak related isolates)
  • dsd_orec [zip, 83 MB] (triplicate spectra from 104 O104:H4 outbreak strain isolates)
  • dsd_ty2482 [zip, 3 MB] (triplicate spectra from 3 biological replicates of O104:H4 isolate TY-2482)
  • dsd_pre-outbreak [zip, 40 MB] (single spectra from 150 pre-outbreak isolates acquired for routine species level ID)
Spectra acquired after sample preparation by formic acid extraction:

  • fae_norec [zip, 150 MB] (triplicate spectra from 190 non-outbreak related isolates)
  • fae_orec [zip, 82 MB] (triplicate spectra from 104 O104:H4 outbreak strain isolates)
  • fae_ty2482 [zip, 3 MB] (triplicate spectra from 3 biological replicates of O104:H4 isolate TY-2482)

Publications

Staphylococcus aureus

References

Wolters M, Rohde H, Maier T, Belmar-Campos C, Franke G, Scherpe S, Aepfelbacher M, Christner M.
MALDI-TOF MS fingerprinting allows for discrimination of major methicillin-resistant Staphylococcus aureus lineages.
Int J Med Microbiol. 2011 Jan;301(1):64-8. Epub 2010 Aug 21. PMID: 20728405

Christner M, Rohde H, Wolters M, Sobottka I, Wegscheider K, Aepfelbacher M.
Rapid identification of bacteria from positive blood culture bottles by use of matrix-assisted laser desorption-ionization time of flight mass spectrometry fingerprinting.
J Clin Microbiol. 2010 May;48(5):1584-91. Epub 2010 Mar 17. PMID: 20237093

External Link