Structural biology aims to interrogate the three-dimensional structure of biomolecules. As many biomolecules regulate biological functions in living organisms, it is crucial to gain insights into the structure to understand how these molecules interact and regulate function. While many techniques exist to interrogate these biomolecules (e.g., x-ray crystallography, NMR), these techniques generally require a lot of sample, or the requirement to crystallise the biomolecule for analysis. Native mass spectrometry (MS) has emerged as a tool to probe intact biomolecules as these biomolecules can be ionised directly from physiological buffers.
Native mass spectrometry has become the powerful technique for the analysis of biomolecules in their physiological states which can give insights into the structure of these biomolecules in the gas-phase. In top-down and native MS, an intact biomolecular ion is formed within the mass spectrometer. These ionised biomolecules can then be interrogated with ion mobility to give insights into the collision cross sectional areas of these molecules. Combining ion mobility with supplemental activation (e.g., electron capture dissociation, collision activated dissociation) allows for fragmentation of the biomolecules at accessible sites. These fragments can then be mapped onto the biomolecule to infer the native structure of these molecules. Here, we demonstrate the use of ion mobility to probe the structure of intact proteins and RNA using ion mobility. The data shown here suggests that native MS with ion-mobility can reveal insights into biomolecular structures in the gas-phase.