Screening for protein variants using mass spectrometry

摘要

A method for screening for variant peptides uses mass spectrometry (MS). A system and a kit may be used for performing the method. Proteins in a sample are digested to form a defined series of peptides. The defined series of peptides are ionized. The ionized species are subjected to collision induced dissociation. Species of known mass/charge ratio are detected to confirm the presence of the protein variant in the original sample.

主权项

1. A method for detecting a known protein variant in a sample, wherein the sequence of the protein variant to be detected is known, the method comprising:
(i) digesting the protein to produce a defined series of peptides; (ii) ionising the peptides and selecting by mass spectrometry an ionised species of known mass/charge ratio indicative of the protein variant; (iii) subjecting the selected ionised species to collision induced dissociation to form a derived ionised species of known mass/charge ratio; and (iv) measuring the derived ionised species of known mass/charge ratio by scanning a window of mass/charge ratios that consists essentially of the known mass/charge ratio of the derived ionised species, wherein presence of the derived ionised species in the window confirms the presence of the protein variant in the sample.