Metallomics: An integrated biometal science

Metallomics is an emerging scientific area integrating the research fields related to the understanding of the molecular mechanisms of metal-associated life processes and the entirety of metal and metalloid species within a cell or tissue type. In metallomics, metalloproteins, metalloenzymes and other metal-containing biomolecules in a biological system are referred to as metallomes, similar to genomes and proteomes in genomics and proteomics, respectively. This review discusses the concept of metallomics with a focus on analytical techniques and methods, particularly the so-called hyphenated techniques which combine a high-resolution separation technique (gel electrophoresis/laser ablation, chromatography or capillary electrophoresis) with a highly sensitive detection method such as elemental (inductively coupled plasma, ICP) or molecular (electron spray ionization (ESI) or matrix-assisted laser desorption/ionization (MALDI)) mass spectrometry, or nuclear X-ray fluorescence/absorption spectrometry. The applications of these advanced analytical methods in the identification of metallo-/phospho-/seleno-proteins, probing of relationships between structure and function of metalloproteins, and study of clinically used metallodrugs will be selectively outlined, along with their advantages and limitations.