Methionine Modifications
The most frequently occurring methionine modification is oxidation. JPT routinely synthesizes all possible oxidation states. To avoid undesired Met oxidation in peptides, we recommend exchanging methionine with its isoster norleucine (Nle).
Please also have a look at our PTM Reference & Kits for direct usage as reference material in mass-spectrometry based proteomics to support PTM proteomics.