Capillary zone electrophoresis-electrospray ionization-tandem mass spectrometry for top-down characterization of the Mycobacterium marinum secretome.
Capillary zone electrophoresis (CZE) with an electrokinetically pumped sheath-flow nanospray interface was coupled with a high-resolution Q-Exactive mass spectrometer for the analysis of culture filtrates from Mycobacterium marinum. We confidently identified 22 gene products from the wildtype M. marinum secretome in a single CZE-tandem mass spectrometry (MS/MS) run. A total of 58 proteoforms were observed with post-translational modifications including signal peptide removal, N-terminal methionine excision, and acetylation. The conductivities of aqueous acetic acid and formic acid solutions were measured from 0.1% to 100% concentration (v/v). Acetic acid (70%) provided lower conductivity than 0.25% formic acid and was evaluated as low ionic-strength and a CZE-MS compatible sample buffer with good protein solubility.
Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States.
Yimeng
Y
Zhao
Liangliang
L
Sun
Matthew M
MM
Champion
Michael D
MD
Knierman
Norman J
NJ
Dovichi
D001426:Bacterial Proteins / Q000737:chemistry*; D019075:Electrophoresis, Capillary; D019910:Mycobacterium marinum / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry; D011499:Protein Processing, Post-Translational; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
D001426:Bacterial Proteins; D010455:Peptides