XL-MS, is a complementary method to high resolution protein structure techniques such as Cryo-EM, NMR and crystallography. XL-MS provides distance constraints and is able to pinpoint residues in close proximity to the interaction interfaces between individual subunits of protein complexes of any size in solution. XL-MS delivers valuable complementary information to enable accurate 3D structural modelling of the proteins or protein complexes. Additionally, XL-MS is a potent tool to identify protein–protein interactions or to uncover protein assemblies in living cells, tissues, or organelles (please see Interactomics section).

The facility offers a complete toolset for performing XL-MS for defining protein-protein interactions (PPIs) and probing PPI interface.