Some proteins are quite attracted to oxygen

As a biopharmaceutical drug developer or researcher, you know that unintended modifications to proteins can reduce the strength or effectiveness of the product you’re developing.

If you’re using proteins that contain the amino acid methionine, you’ll probably need to find out what level of oxidation has taken place. This is because it’s quite natural and easy for methionine to acquire additional oxygen atoms when exposed to air. And such oxidation leads to a change in the hydrophobicity and mass of proteins, possibly reducing the impact of your product.

Whilst not as demanding to analyze as deamidation, we can generate an excellent synopsis of the levels of oxidation occurring in your proteins. We look at it firstly by peptide mapping or RP-HPLC and then we determine the relative amount of oxidation by UV or by mass spectrometry.

Analyzing methionine oxidation is a key requirement of ICHQ6B.

Technical information

Oxidation of proteins is usually observed in methionine residues and to a lesser extent in tryptophan or tyrosine. As the name suggests, it is promoted by a form of oxygen, such as peroxide, but is also influenced by light, pH, temperature, buffers and other factors.

In many proteins, methionines in certain positions of an amino acid are especially prone to oxidation, presumably due to differences in solvent accessibility.

Your contact for Oxidation at Protagen Protein Services GmbH


Dr. Marcus Mreyen

Director Business Development
Our business development team will be happy to assist you with your project.

Phone: +49 (0) 231 9742-6100