Protein Identification by LC-MS/MS
Protein identification by precursor peptide fragmentation (MS/MS) following protein digestion with trypsin.
|Research Objectives||Identification of protein(s) in sample|
LC-MS/MS is an analytical technique used for protein identification. A purified protein or complex mixture of proteins is digested into peptide fragments. During MS and subsequent MS/MS analysis high accuracy precursor mass data and fragment ion spectra are obtained. By matching theoretical spectra in known sequence databases to experimental spectra using search algorithms, peptide identity and consequently protein identity can be obtained.
Samples are first prepared for protein digestion by trypsin. Depending on the complexity of the protein mixture, protein samples are subjected to one- dimensional or two-dimensional fractionation to simplify the protein mixture prior to MS analysis.
An analytical report is provided that contains information regarding the identified protein(s) and all relevant experimental procedures.
- Samples for in-gel digest must be submitted as gel slices measuring 1mm x 1mm x 1mm stained with a mass spectrometry compatible stain. Samples for in-solution digest must be presented free of salts, reducing agents and detergents at a concentration of 1 mg/ml at a minimum volume of 25 µl. If excipients are present, please inform us as this will influence our sample preparation.