Quantification of proteins by data independent acquisition: Performance assessment of the Hi3 methodology.

Proteomics greatly benefited from the development of mass spectrometry. Over the last years, data-independent acquisitions increased in popularity in an effort to provide routine label free quantitative information. In this report, the performance of the Hi3 label free method was assessed based on the analysis of a plasma-derived protein mixture.

Mass spectrometry based analysis of human plasma-derived factor X revealed novel post-translational modifications.

Human coagulation factor X is a central component of the blood coagulation cascade that converts, under its activated form, prothrombin into thrombin. Generation of thrombin is the final step of the clotting cascade that leads to the clot by polymerization of fibrinogen molecules into a fibrin network. Today, research of new by-passing agents of the coagulation may contribute to an increased interest for human factor X, which may, in consequence, lead to the need of a more exhaustive picture of its structural features.

Fast analysis of recombinant monoclonal antibodies using IdeS proteolytic digestion and electrospray mass spectrometry.

We describe a fast and informative method to investigate the posttranslational modifications of monoclonal antibodies (MAbs). The MAb is first digested by a specific enzyme that cleaves heavy chains under the hinge domain. After reduction of disulfide bridges, three polypeptide chains of approximately 25 kDa are released and analyzed by liquid chromatography-mass spectrometry (LC-MS).