title: Structural modeling of heteromeric protein complexes from disassembly pathways and ion mobility-mass spectrometry.
abstract: Structure determination of macromolecular protein assemblies remains a challenge for well-established methods. Here, we provide an assessment of an emerging structural technique, ion mobility-mass spectrometry (IM-MS), and examine the use of collision cross-sections (CCSs), derived from IM-MS, as restraints for structure characterization of heteromeric protein assemblies. Using 15 complexes selected from the Protein Data Bank, we validate the use of low-resolution models by comparing their CCSs with those calculated for all-atom structures. We then select six heteromeric complexes, disrupting them in solution to form subcomplexes. Experimental and calculated CCSs reveal close similarity for 18 of the 21 (sub)complexes. Exploring the use of CCS as a restraint, we incorporate it into a scoring function and show good correlation between the score and similarity to the native structure for heteromers, especially when an additional symmetry restraint was introduced.
authors: Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3QZ, UK.
authors: Zoe
authors: Z
authors: Hall
authors: Argyris
authors: A
authors: Politis
authors: Carol V
authors: CV
authors: Robinson
mesh_terms: D000465:Algorithms; D019540:Area Under Curve; D003198:Computer Simulation; D049308:Dioxygenases / Q000737:chemistry; D013058:Mass Spectrometry; D008958:Models, Molecular; D009010:Monte Carlo Method; D046912:Multiprotein Complexes / Q000737:chemistry*; D020836:Protein Structure, Quaternary; D012372:ROC Curve; D014367:Tryptophan Synthase / Q000737:chemistry
chemical_list: D046912:Multiprotein Complexes; D049308:Dioxygenases; D014367:Tryptophan Synthase