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Pelzing, M.

Publications and source records attributed to Pelzing, M..

2 recordsLinked to original sources

Structural basis for inhibition of βFXIIa by garadacimab

FXIIa is the principal initiator of the plasma contact system and can activate both procoagulant and proinflammatory pathways. Its activity is important in the pathophysiology of Hereditary Angioedema (HAE). Here, we describe a high-resolution cryo-EM structure of the beta-chain from FXIIa ({beta}FXIIa) complexed with the Fab fragment of garadacimab. Garadacimab binds to {beta}FXIIa through an unusually long CDR-H3 that inserts into the S1 pocket in a non-canonical way. This atypical structural mechanism is likely the primary contributor in the inhibition of activated FXII proteolytic activity in HAE. Garadacimab Fab-{beta}FXIIa structure also reveals critical determinants of high-affinity binding of garadacimab to activated FXII. Structural analysis with other bonafide FXIIa inhibitors, such as benzamidine and C1-INH, reveals a conserved mechanism of {beta}FXIIa inhibition, a novel finding of this study. In summary, garadacimab Fab-{beta}FXIIa structure provides crucial insights into its mechanism of action and delineates primary and auxiliary paratopes/epitopes. This work reaffirms the benefits of cryo-EM as a primary tool to study antigen-antibody complexes in near native state, particularly where other methods have fallen short.

biochemistry↗

Cross-linking/Mass Spectrometry: A Community-Wide, Comparative Study Towards Establishing Best Practice Guidelines

The number of publications in the field of chemical cross-linking combined with mass spectrometry (XL-MS) to derive constraints for protein three-dimensional structure modeling and to probe protein-protein interactions has largely increased during the last years. As the technique is now becoming routine for in vitro and in vivo applications in proteomics and structural biology there is a pressing need to define protocols as well as data analysis and reporting formats that are generally accepted in the field and that have shown to lead to high-quality results. This first, community-based harmonization study on XL-MS is based on the results of 32 groups participating worldwide. The aim of this paper is to summarize the status quo of XL-MS and to compare and evaluate existing cross-linking strategies. From the results obtained, common protocols will be established. Our study serves as basis for establishing best practice guidelines in the field for conducting cross-linking experiments, performing data analysis, and reporting formats with the ultimate goal of assisting scientists to generate accurate and reproducible XL-MS results.

biochemistry↗