Protein Structure Identification

The application of bottom-up proteomics analysis strategies is limited by incomplete or ambiguous characterization of splice variants, diverse post-translational modifications, and endogenous protein cleavage. With advancements in analytical tools, top-down strategies have gained more application. Besides the FT-ICR mass spectrometer, the invention and innovation of the Orbitrap mass spectrometer have driven the development of top-down proteomics.

Protein Structure Identification

Since proteins do not require digestion before analysis, employing top-down strategies can retain and detect information lost in shotgun methods, such as disulfide-bonded quaternary structures. This is a unique advantage of the top-down approach in characterizing post-translational modifications like disulfide bonds at the protein level. It has also led to increased application of the top-down method in QC analysis of protein therapeutics, such as insulin, to ensure correct expression, folding, and assembly of recombinant proteins.

Biotech company Biotech-Peak employs Thermo Fisher's Orbitrap Fusion Lumos mass spectrometry platform combined with nanoLC-MS/MS nano-liquid chromatography to provide top-down protein structure characterization services.