Increasing evidence shows that protein phosphorylation on serine, threonine and tyrosine residues is a major regulatory post-translational modification in the bacteria. This review focuses on the implications of bacterial phosphoproteome in bacterial pathogenicity and highlights recent development of methods in phosphoproteomics and the connectivity of the phosphorylation networks. Recent technical developments in the high accuracy mass spectrometry have dramatically transformed proteomics and made it possible the characterization of a few exhaus- tive site-specific bacterial phosphoproteomes. The high abundance of tyrosine phosphorylations in a few bacterial phosphoproteomes suggests their roles in the pathogenicity, especially in the case of pathogen-host interactions; the high abundance of multi-phosphorylation sites in bacterial phosphoprotein is a compensation of the relatively small phosphorylation size and an indicator of the delicate regulation of protein functions.
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 metal-loproteins,and study of clinically used metallodrugs will be selectively outlined,along with their advantages and limitations.
GE RuiGuang1,2 & SUN HongZhe1 1 Department of Chemistry and Open Laboratory of Chemical Biology,The University of Hong Kong,Hong Kong,China