This presentation will demonstrate two applications of native mass spectrometry (nMS) as an advanced platform technology to characterise intact biomolecular complexes important in drug discovery. This capability is established within the Ramaciotti Australian Native Mass Spectrometry Platform for Health Discoveries at Griffith University.
Targeted Protein Degradation: The binding of proteolysis targeting chimeras (PROTACs) to their partner ubiquitin E3 ligase (E3) and protein of interest (POI) followed by coordination to an E2 conjugating enzyme loaded with Ub (E2-Ub) is essential in the mechanism of ubiquitination and degradation. Despite the importance of the full multiprotein POI-PROTAC-E3-E2-Ub complex, methods to capture this species at scale are lacking. In this talk we leverage the benefits of native mass spectrometry (nMS) as a ‘show all’ approach to characterise all protein complexes central to PROTAC development. Significantly, the nMS methods use native proteins without any requirement for protein modification and captures all equilibrium species in a single mass spectrum
Covalent ligand screening: Covalent binders impart different practical considerations for screening when compared to noncovalent binders, and there is a need for methods to characterise direct target engagement. In this talk I will demonstrate the application of nMS for covalent screening of electrophilic fragments that modify cysteine. The nMS method can assess protein binding, protein specificity and supports identification of the site of protein modification (utilising mutant proteins).