Characterization of novel +70 DA modification

31 August 2021

New article by scientists at Alphalyse on using mass spectrometry to measure a product-related impurity in a novel biologic:

𝐂𝐡𝐚𝐫𝐚𝐜𝐭𝐞𝐫𝐢𝐳𝐚𝐭𝐢𝐨𝐧 𝐨𝐟 𝐚 𝐧𝐨𝐯𝐞𝐥 + 𝟕𝟎 𝐃𝐚 𝐦𝐨𝐝𝐢𝐟𝐢𝐜𝐚𝐭𝐢𝐨𝐧 𝐢𝐧 𝐫𝐡𝐆𝐌-𝐂𝐒𝐅 𝐞𝐱𝐩𝐫𝐞𝐬𝐬𝐞𝐝 𝐢𝐧 𝐄. 𝐜𝐨𝐥𝐢:

Authors: Magdalena Widgren Sandberg, Jakob Bunkenborg, Stine Thyssen, Martin Villadsen and Thomas Kofoed

The scientists found and identified a novel post-translational modification in fermentation batches of Granulocyte-macrophage colony-stimulating factor (GM-CSF) recombinantly expressed in E. coli.

The modification gave a mass shift of + 70 Da. Peptide mapping analysis demonstrated its location to the protein N-terminus and lysine side chains.

Full article (open access):

This study shows the importance of good analytics to detect and monitor product-related impurities during biologics development.