title: Identification of proteins in cell-free extracts using liquid chromatography-electrospray ionization mass spectrometry.
abstract: A rapid method for the identification and characterization of proteins in bacterial cell-free extracts has been developed using directly combined liquid chromatography-electrospray mass spectrometry. The usefulness of this technique is demonstrated for monitoring the expression and chemical modification of phosphoenolpyruvate-sugar phosphotransferase system (PTS) proteins from E. coli with molecular masses ranging from 9-65 kDa. The technique is characterized by minimal sample preparation, remarkable mass accuracy and resolution, reproducibility and the ability, unlike gel electrophoresis, to directly identify posttranslational modifications. The advantages of this technique over analogous matrix-assisted laser desorption ionization mass spectrometry approaches and its potential as a standard tool in the biomolecular research laboratory are discussed.
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, MD, USA. joseph.dalluge@nist.gov
authors.forename: J J
authors.initials: JJ
authors.lastname: Dalluge
authors.forename: P
authors.initials: P
authors.lastname: Reddy
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis*; D002853:Chromatography, Liquid / Q000379:methods*; D004926:Escherichia coli; D015964:Gene Expression Regulation, Bacterial; D013058:Mass Spectrometry; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000032:analysis; D010766:Phosphorylation; D011994:Recombinant Proteins / Q000032:analysis; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D001426:Bacterial Proteins; D011994:Recombinant Proteins; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System