AVS 52nd International Symposium
    Biomaterial Interfaces Monday Sessions
       Session BI-MoP

Paper BI-MoP5
Pulsed RF Plasma-Modified Surfaces for On-Probe Fractionation and MALDI Mass Spectrometric Characterization of Bacterial Proteins

Monday, October 31, 2005, 5:00 pm, Room Exhibit Hall C&D

Session: Biomaterial Interfaces Poster Session
Presenter: G.S. Fernando, Southern Illinois University Carbondale (SIUC)
Authors: G.S. Fernando, Southern Illinois University Carbondale (SIUC)
L.G. van Waasbergen, University of Texas at Arlington
R.B. Timmons, University of Texas at Arlington
G.R. Kinsel, Southern Illinois University Carbondale (SIUC)
Correspondent: Click to Email
Mass spectrometric characterization of bacteria is of growing importance, not only for applications in basic research but also as a means for rapid, unambiguous identification of bacterial pathogens. In this study, crude protein mixtures from cyanobacteria Synechocystis sp. strain PCC 6803 are characterized by Matrix-Assisted Laser Desorption Ionization Mass Spectrometry (MALDI-MS) following fractionation directly on the surface of pulsed RF plasma polymer modified On-Probe Affinity Capture (OPAC) MALDI probes. Pulsed RF plasma polymer deposition allows the incorporation of a wide diversity of surface chemistries and functional group densities directly on the surface of the OPAC MALDI probe, which can be subsequently used to selectively capture subpopulations of a complex protein mixture - for example, as derived from a bacterial source. OPAC protein mixture fractionation can be based on broad chemical properties (e.g. hydrophobic / hydrophilic, acid / base) or on highly bioselective interactions (e.g. metal binding properties, protein-substrate interactions). With careful optimization of the protein mixture deposition and washing procedures, fingerprint MALDI mass spectra of the bacteria proteome can be recorded which contain unique peptide and protein signature ions, not observed in the MALDI mass spectrum of the crude bacterial protein extract. The simplicity, speed and high sensitivity of the OPAC MALDI approach makes it an attractive option for bacterial proteome characterization.