MALDI-FTMS of whole-cell bacteria

by Jones, Jeffrey J.; Stump, Michael J.; Wilkins, Charles L.

A review. For years scientists have sought to develop rapid and accurate means of detecting and characterizing microorganisms. Taxonomic identification of pure bacteria has become possible through the use of matrix-assisted laser desorption/ionizationmass spectrometry, directly detecting abundant proteins and other components that comprise cells during rapid cellular growth. Recently, MALDI Fourier transform mass spectrometry (FTMS) of environmental samples has proved its advantage, showing that high resoln. is the answer to making accurate assignments in complex mixts. FTMS takes whole-cell identification one step further by allowing assignment of mol. identities to obsd. masses. For proteins, accurate mass detn. coupled with high resoln., eliminates the ambiguity that can arise from other components interfering with the assignment to known protein or lipid constituents. With its improved mass accuracy and much higher resolving power than MALDI-TOF mass spectrometry, FTMS allows use of specifically identified biomarkers for bacterial taxonomic purposes, a significant improvement over "fingerprint" approaches based on use of patterns of unidentified substances.