Identification of mammalian cell lines using MALDI-TOF and LC-ESI-MS/MS mass spectrometry.
Direct mass spectrometric analysis of complex biological samples is becoming an increasingly useful technique in the field of proteomics. Matrix-assisted laser desorption/ionization mass spectroscopy (MALDI-MS) is a rapid and sensitive analytical tool well suited for obtaining molecular weights of peptides and proteins from complex samples. Here, a fast and simple approach to cellular protein profiling is described in which mammalian cells are lysed directly in the MALDI matrix 2,5-dihydroxybenzoic acid (DHB) and mass analyzed using MALDI-time of flight (TOF). Using the unique MALDI mass spectral "fingerprint" generated in these analyses, it is possible to differentiate among several different mammalian cell lines. A number of techniques, including MALDI-post source decay (PSD), MALDI tandem time-of-flight (TOF-TOF), MALDI-Fourier transform ion cyclotron resonance (FTICR), and nanoflow liquid chromatography followed by electrospray ionization and tandem mass spectrometry (LC-ESI-MS/MS) were employed to attempt to identify the proteins represented in the MALDI spectra. Performing a tryptic digestion of the supernatant of the cells lysed in DHB with subsequent LC-ESI-MS/MS analysis was by far the most successful method to identify proteins.
Zhang
Xu
X
Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, 53706-1396, Madison, WI, USA.
Scalf
Mark
M
Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, 53706-1396, Madison, WI, USA.
Berggren
Travis W
TW
Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, 53706-1396, Madison, WI, USA.
Westphall
Michael S
MS
Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, 53706-1396, Madison, WI, USA.
Smith
Lloyd M
LM
Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, 53706-1396, Madison, WI, USA. smith@chem.wisc.edu.
D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line / Q000737:chemistry*; D002853:Chromatography, Liquid / Q000379:methods; D006224:Cricetinae; D005583:Fourier Analysis; D006801:Humans; D020014:K562 Cells; D008969:Molecular Sequence Data; D010449:Peptide Mapping / Q000379:methods*; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification; D011506:Proteins / Q000737:chemistry / Q000302:isolation & purification; D040901:Proteomics / Q000379:methods; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
D010455:Peptides; D011506:Proteins