title: ProteoPlex: stability optimization of macromolecular complexes by sparse-matrix screening of chemical space.
abstract: Molecular machines or macromolecular complexes are supramolecular assemblies of biomolecules with a variety of functions. Structure determination of these complexes in a purified state is often tedious owing to their compositional complexity and the associated relative structural instability. To improve the stability of macromolecular complexes in vitro, we present a generic method that optimizes the stability, homogeneity and solubility of macromolecular complexes by sparse-matrix screening of their thermal unfolding behavior in the presence of various buffers and small molecules. The method includes the automated analysis of thermal unfolding curves based on a biophysical unfolding model for complexes. We found that under stabilizing conditions, even large multicomponent complexes reveal an almost ideal two-state unfolding behavior. We envisage an improved biochemical understanding of purified macromolecules as well as a substantial boost in successful macromolecular complex structure determination by both X-ray crystallography and cryo-electron microscopy.
authors.affiliation: Research Group of 3D Electron Cryomicroscopy, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.
authors.forename: Ashwin
authors.initials: A
authors.lastname: Chari
authors.affiliation: Research Group of 3D Electron Cryomicroscopy, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.
authors.forename: David
authors.identifier: http://orcid.org/0000-0002-5276-5633
authors.initials: D
authors.lastname: Haselbach
authors.affiliation: Research Group of 3D Electron Cryomicroscopy, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.
authors.forename: Jan-Martin
authors.initials: JM
authors.lastname: Kirves
authors.affiliation: Department of Biochemistry, Theodor-Boveri Institute, University of Würzburg, Würzburg, Germany.
authors.forename: Juergen
authors.initials: J
authors.lastname: Ohmer
authors.affiliation: Department of Biochemistry, Theodor-Boveri Institute, University of Würzburg, Würzburg, Germany.
authors.forename: Elham
authors.initials: E
authors.lastname: Paknia
authors.affiliation: Research Group of 3D Electron Cryomicroscopy, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.
authors.forename: Niels
authors.identifier: http://orcid.org/0000-0002-4609-4052
authors.initials: N
authors.lastname: Fischer
authors.affiliation: Institut für Chemie und Biochemie, Freie Universität Berlin, Berlin, Germany.
authors.forename: Oleg
authors.initials: O
authors.lastname: Ganichkin
authors.affiliation: Institut für Zoologie - Abteilung für Molekular Tierphysiologie, Johannes Gutenberg Universität Mainz, Mainz, Germany.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Möller
authors.affiliation: Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.
authors.forename: Jeremiah J
authors.initials: JJ
authors.lastname: Frye
authors.affiliation: Research Institute of Molecular Pathology, Vienna, Austria.
authors.forename: Georg
authors.initials: G
authors.lastname: Petzold
authors.affiliation: Research Institute of Molecular Pathology, Vienna, Austria.
authors.forename: Marc
authors.initials: M
authors.lastname: Jarvis
authors.affiliation: Department for Bioanalytics, Georg-August University Göttingen, Göttingen, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Tietzel
authors.affiliation: Department of Biochemistry, Theodor-Boveri Institute, University of Würzburg, Würzburg, Germany.
authors.forename: Clemens
authors.initials: C
authors.lastname: Grimm
authors.affiliation: Research Institute of Molecular Pathology, Vienna, Austria.
authors.forename: Jan-Michael
authors.initials: JM
authors.lastname: Peters
authors.affiliation: Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.|Howard Hughes Medical Institute, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.
authors.forename: Brenda A
authors.initials: BA
authors.lastname: Schulman
authors.affiliation: Department for Bioanalytics, Georg-August University Göttingen, Göttingen, Germany.
authors.forename: Kai
authors.initials: K
authors.lastname: Tittmann
authors.affiliation: Institut für Zoologie - Abteilung für Molekular Tierphysiologie, Johannes Gutenberg Universität Mainz, Mainz, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Markl
authors.affiliation: Department of Biochemistry, Theodor-Boveri Institute, University of Würzburg, Würzburg, Germany.
authors.forename: Utz
authors.initials: U
authors.lastname: Fischer
authors.affiliation: Research Group of 3D Electron Cryomicroscopy, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.
authors.forename: Holger
authors.initials: H
authors.lastname: Stark
mesh_terms: D000465:Algorithms; D001665:Binding Sites; D003198:Computer Simulation; D003460:Crystallization; D008956:Models, Chemical; D008958:Models, Molecular; D046912:Multiprotein Complexes / Q000737:chemistry* / Q000648:ultrastructure*; D011485:Protein Binding; D011487:Protein Conformation; D017510:Protein Folding; D012984:Software
chemical_list: D046912:Multiprotein Complexes