The Staphylococcus aureus secretome - TI Pharma

Chapter 3
Figure 1. Characterization of extracellular proteomes of different clinical S. aureus isolates. Cells were grown
in TSB medium to an OD 540 of 10. Proteins in culture supernatants were collected by TCA precipitation. 350 µg of
the protein extract of each strain was separated on 2D gels, using commercially available IPG strips (pH 3-10,
GE-Healthcare, Sweden) for the first dimension. Protein spots were detected by staining with colloidal Coomassie
Brillant Blue. For protein identification, individual protein spots were excised from the gel and digested with
trypsin. The resulting peptide solution was analyzed by tandem mass spectrometry on a Proteome Analyzer
4700/4800 (Applied Biosystems, USA). The respective strain is indicated in the upper left corner of each gel.
Altogether 206 distinct proteins were identified (Supplemental table IVb). 107 of these
proteins showed signal peptides typical for Sec-translocated proteins. Using PSORTb
software (http://www.psort.org/psortb), 63 of the Sec-translocated proteins were predicted to
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