MAR 11, 2024

Comparison of Protein Sequencing vs. Mass Spectrometry

WRITTEN BY: Sarah Hoffman
While MS has become the gold standard for protein identification, several confounding factors can limit the unambiguous, proteome-wide mapping of peptides. For example, missed or unanticipated cleavages, chemical modifications, and post-translational modifications (PTMs) can lead to peptides that are not detected by the search algorithm. Amino acids of identical or similar masses also present challenges in standard MS workflow. Examples include the differentiation of isoleucine and leucine, asymmetric dimethylarginine and symmetric dimethylarginine, and trimethyllysine and acetyllysine. Furthermore, chemical modifications may result from LC-MS ionization, such as the modification from glutamine to pyroglutamate. These changes could be missed when using default databases and analysis settings.

Click here to continue reading...