Burkholderia cenocepacia is an opportunistic pathogen that may cause severe complications for cystic fibrosis patients. We aim to apply proteomic technology to identify proteins that are secreted by the type III en IV secretion systems and consequently injected in the host cell. We will study the influence of environmental conditions on the levels of virulence factors and determine their effect on the viability of the host cell and on its immune response. Our basic research is meant to evaluate the potential of secretion systems as future antibiotic targets.