Some bacteria such as Cupriavidus metallidurans CH34 developed mechanisms of resistance to (toxic) metal ions allowing them to live in polluted environment but also to escape the biocidal activity of metal ions, like silver or copper, used as sanitizing agents. We are focusing on the study of protein complexes involved in the regulated transport of metal ions out of the cell. Proteins associated with different heavy metal resistance systems were discovered by a differential proteomic approach. The proteins have been overexpressed and purified.
Recently we obtained structures by X-ray diffraction and NMR, shedding light on metal ion transport mechanism (De Angelis et al., 2010; Bersch et al., 2011).