Proteomic Analysis to Investigate Regulatory Networks in Staphylococcus aureus

The analysis of the expression of virulence genes and the elucidation of metabolic and regulatory pathways of Staphylococcus aureus provide us with important information about the interaction between the pathogen and its host, mechanisms by which this organism causes diseases, and the resistance to antibiotics. In order to investigate regulatory networks of S. aureus , we analyze the cytoplasmic and extracellular proteome by using two-dimensional (2D) gel analyses combined with matrix-assisted laser ionization–time-of-flight mass spectrometry (MALDI–TOF MS). Gel-based proteomics is an extremely valuable tool in microbial physiology that can, in combination with various visualization and quantitation software packages, very rapidly provide comparative and quantitative data for multi-sample comparison.