“…Artificial covalent modification of proteins is an arduous but fruitful task of major interest for the biophysics and biochemistry communities that normally pursue as goals the detection or purification of the protein itself in order to have a more thorough understanding of molecular mechanisms and the expansion of the applicability of such biomolecules. Despite the intrinsic difficulties associated to perform those chemical modifications of proteins, the attachment of analytical or engineered probes for protein tracking (labelling) (Giepmans et al, 2006;Waggoner, 2006;Wu & Goody, 2010) or protein profiling (chemical proteomics) (Evans & Cravatt, 2006;Cravatt et al, 2008), the introduction of affinity tags for separation-isolation of proteins (affinity chromatography) (Azarkan et al, 2007;Fang & Zhang, 2008) or for mass spectroscopy-based protein identification and characterization (chemical tagging) (Leitner & Lindner, 2006), the immobilization onto solid supports (microarray technologies) (Wong et al, 2009) and the conjugation with other biomolecules (post-translational modifications) (Gamblin et al, 2008b;Walsh, 2009;Heal & Tate, 2010) are among some of the most useful and frontier techniques and methodologies used in Proteomics. For the chemical modification of proteins, a large number of strategies are nowadays available (Hermanson, 2008).…”