title: The emerging role of ICP-MS in proteomic analysis.
abstract: Quantitative proteomics and absolute determination of proteins are topics of fast growing interest, since only the quantity of proteins or changes in their abundance reflect the status and extent of changes of a given biological system. Quantification of the desired proteins has been carried out by molecule specific MS techniques, but relative quantifications are commonplace so far even resorting to stable isotope labelling techniques such as ICAT and SILAC. In the last decade the idea of using element-selective mass spectrometric detection (e.g. ICP-MS instruments) to achieve absolute quantification has been realised and ICP-MS stands now as a new tool in the field of quantitative proteomics. In this review the emerging role of ICP-MS in protein and proteomic analysis is highlighted. The potential of ICP-MS methods and strategies for screening multiple heteroatoms (e.g. S, P, Se, metals) in proteins and their mixtures and extraordinary capabilities to tackle the problem of absolute protein quantifications, via heteroatom determinations, are discussed and illustrated. New avenues are also open derived from the use of ICP-MS for precise isotope abundance measurements in polyisotopic heteroatoms. The "heteroatom (isotope)-tagged proteomics" concept is focused on the use of naturally present element tags and also extended to any protein by resorting to bioconjugation reactions (i.e. labelling sought proteins and peptides with ICP-MS detectable heteroatoms). A major point of this review is displaying the possibilities of using a "hard" ion source, the ICP, to complement well-established "soft" ion sources for mass spectrometry to tackle present proteomic analysis.
authors.affiliation: Department of Physical and Analytical Chemistry, University of Oviedo, Oviedo, Spain.
authors.forename: Jörg
authors.initials: J
authors.lastname: Bettmer
authors.forename: María
authors.initials: M
authors.lastname: Montes Bayón
authors.forename: Jorge Ruiz
authors.initials: JR
authors.lastname: Encinar
authors.forename: María Luisa
authors.initials: ML
authors.lastname: Fernández Sánchez
authors.forename: María del Rosario
authors.initials: Mdel R
authors.lastname: Fernández de la Campa
authors.forename: Alfredo
authors.initials: A
authors.lastname: Sanz Medel
mesh_terms: D000818:Animals; D049872:Bivalvia; D002138:Calibration; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*; D008667:Metalloproteins / Q000737:chemistry; D008670:Metals / Q000737:chemistry; D010455:Peptides / Q000737:chemistry; D010758:Phosphorus / Q000737:chemistry; D011506:Proteins / Q000737:chemistry; D020543:Proteome; D040901:Proteomics / Q000379:methods*; D015203:Reproducibility of Results; D012643:Selenium / Q000737:chemistry; D013455:Sulfur / Q000737:chemistry
chemical_list: D008667:Metalloproteins; D008670:Metals; D010455:Peptides; D011506:Proteins; D020543:Proteome; D010758:Phosphorus; D013455:Sulfur; D012643:Selenium