Title: |
ICP-MS - A useful tool for quantitative phosphoproteomics? |
| Author(s): |
A. Raab, L. Griffin, B. Platt and J. Feldmann |
| Year: |
2019 |
| Conference name: |
ReMind 2019 Biomolecules in Neurodegenerative Diseases |
| Conference place: |
Physikalisch-Technische Bundesanstalt, Germany |
| Conference date: |
26./27.06.2019 |
| Abstract: |
Accurate quantification of proteins and their post-translational protein modifications (PTMs) is an active field in a range of research areas. Especially in the biochemical / medial field significant work in this area is happening.
The major route to quantification so far is “bottom-up” protein identification via databases and quantification via spiking of the sample with the peptide(s) of interest labelled with stable isotope(s). For relative quantification of proteins in different samples the proteins/peptides in each sample can be labelled using different isotope tags. The first approach requires the availability of the labelled peptide(s) of interest which might make it impractical to apply for none-targeted protein quantification.
Elemental determination of proteins /peptides in contrast relies on the presence of generally ICP-MS accessible elements. In the field of proteomics these are predominantly sulphur, from methionine and cysteine, and phosphorus from PTMs. For absolute quantification of these elements simple element solutions can be used, or in the case of sulphur isotope dilution (ID)-MS. Quantification by ICP-MS would also allow a complete mass balance to estimate protein losses during sample preparation. Protein losses during sample preparation are difficult to avoid due to the multiple steps required especially when enrichment methods are used. Results of different phosphopeptide enrichment methods will be presented. |
