Microbial metalloproteomes explored using MIRAGE

Metalloproteomics is a rapidly developing field of science that involves the comprehensive analysis of all metal-containing or metal-binding proteins in a biological sample. The purpose of this review is to offer an overview of the research involving Metal Isotope native RadioAutography in Gel Electrophoresis (MIRAGE), a powerful new method to visualize and study the proteome of a particular metal ion. MIRAGE involves four steps: i) labelling of target proteins with a radioisotope; ii) separation of intact holo-proteins using native isoelectric focusing (1D) combined with Blue Native PAGE (2D); iii) spot visualization and quantification using autoradiography; and iv) protein identification by tandem mass spectrometry. MIRAGE Investigations of the soluble Cu, Zn, and Fe metalloproteomes of Escherichia coli, and of the soluble Mo and W proteomes of the hyperthermophilic archaeon Pyrococcus furiosus are reviewed.