DC Biosciences PTM services enable you to answer your questions about Post-Translational Modifications.
Post-Translational Modifications (PTMs) are an often overlooked dimension of proteomics, yet they have a huge impact on protein function.
MS analysis of PTMs usually relies on specific sample enrichment.
The diversity and relative rarity of modified peptides make them difficult to study. In addition, unraveling complex modifications, such as glycosylation or ubiquitinylation, can be challenging. Since “bottom-up” proteomics relies on sample digestion into peptides, it can also be difficult to identify the relationships between different modified sites on the same protein.
PTM detection by MS is improved by selectively enriching for modified peptides or proteins using a variety of methods (affinity resins, chromatography etc.). The PTM-enriched fraction is then analysed separately from the flow-through or the non-enriched sample.
Importantly, when analysing MS data, PTMs which are not searched for will not be identified. Including too many modifications in a search can increase the false discovery rate while slowing down the search. It is therefore important to think carefully about which modifications to search for.
The most-studied PTMs are phosphorylation, ubiquitinylation (and modification by ubiquitin-like proteins) and the varied types of glycosylation. Others, such as hydroxylation are emerging as new research foci.