This technique is used to characterise disulphide folding pattern, i.e., an analysis of which Cys residues are linked.
Scope of work:
For analysis we require the full theoretical protein sequence, and postulated S-S bridging patterns.
Request Form: Disulphide Bridge Analysis
Identification of phosphorylation sites on protein and peptide samples is achieved through precursor ion and neutral loss scans that allow detection of the loss of the phosphate group. From this data, phosphorylation sites can be mapped to detect this important post-translational modification of proteins.
For phosphorylation detection we use a LC-MS/MS system (4000Q-Trap [Sciex]). Our approach is first to perform protein identification by tandem MS (as per our standard service). This enables confirmation of protein identity prior to detection of the phosphorylated peptides.
Request Form: Phosphorylation Detection
We recommend protein bands or spots are of sufficient concentration to be detected by Coomassie G250 staining. Two bands are required to enable the initial protein identification, although less material can be used for that process. Larger amounts of material increase the probability of achieving a successful result.