Publications by authors named "A Konijnenberg"
Article Synopsis
- Ion mobility mass spectrometry (IM-MS) is a technique that helps analyze native proteins by their size and shape, focusing on individual molecules and their collision cross sections.
- While it can reveal the structural variety of proteins like prolyl oligopeptidase in solutions, IM-MS is unable to detect this conformational heterogeneity.
- The study suggests that assessing how cysteines become protected when ligands bind could lead to new methods for screening potential drugs using mass spectrometry.
Native mass spectrometry (MS) has become widely accepted in structural biology, providing information on stoichiometry, interactions, homogeneity, and shape of protein complexes. Yet, the fundamental assumption that proteins inside the mass spectrometer retain a structure faithful to native proteins in solution remains a matter of intense debate. Here, we reveal the gas-phase structure of β-galactosidase using single-particle cryo-electron microscopy (cryo-EM) down to 2.
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- Advances in electron cryomicroscopy (cryo-EM) and single-particle analysis (SPA) face challenges due to sample heterogeneity that affect achieving high-resolution structures.
- The study introduces native electrospray ion-beam deposition (native ES-IBD) as a promising technique for preparing high-purity protein samples through mass selection in vacuum.
- Although native ES-IBD shows potential for improved cryo-EM analysis, challenges in resolving structural variations still need to be addressed to match traditional cryo-EM resolution standards.*
The Two-Partner secretion pathway mediates protein transport across the outer membrane of Gram-negative bacteria. TpsB transporters belong to the Omp85 superfamily, whose members catalyze protein insertion into, or translocation across membranes without external energy sources. They are composed of a transmembrane β barrel preceded by two periplasmic POTRA domains that bind the incoming protein substrate.
View Article and Find Full Text PDFRecent interest in biological and synthetic DNA nanostructures has highlighted the need for methods to comprehensively characterize intermediates and end products of multimeric DNA assembly. Here we use native mass spectrometry in combination with ion mobility to determine the mass, charge state and collision cross section of noncovalent DNA assemblies, and thereby elucidate their structural composition, oligomeric state, overall size and shape. We showcase the approach with a prototypical six-subunit DNA nanostructure to reveal how its assembly is governed by the ionic strength of the buffer, as well as how the mass and mobility of heterogeneous species can be well resolved by careful tuning of instrumental parameters.
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