title: Structure of an influenza neuraminidase-diabody complex by electron cryomicroscopy and image analysis.
abstract: The structure of a complex between a bivalent diabody and its antigen, influenza neuraminidase, has been determined by electron cryomicroscopy of single particles and image analysis. A three-dimensional reconstruction has been interpreted in terms of high-resolution X-ray models of the component proteins. The complex consists of two neuraminidase tetramers cross-linked by four diabodies with 422 point symmetry. The structure and symmetry of the complex is determined uniquely by packing constraints consistent with the maximum possible number of diabody cross-links. Diabodies may provide a useful approach to the structure determination of small proteins by incorporating the proteins into large symmetric complexes followed by single-particle electron microscopy.
authors.affiliation: MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK. rose@mrc-lmb.cam.ac.uk
authors.forename: Peter B
authors.initials: PB
authors.lastname: Rosenthal
authors.forename: Lynne J
authors.initials: LJ
authors.lastname: Waddington
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Hudson
mesh_terms: D020285:Cryoelectron Microscopy; D007128:Immunoglobulin Fragments / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D046911:Macromolecular Substances; D008958:Models, Molecular; D009439:Neuraminidase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D009975:Orthomyxoviridae / Q000201:enzymology*; D020836:Protein Structure, Quaternary
chemical_list: D007128:Immunoglobulin Fragments; D046911:Macromolecular Substances; D009439:Neuraminidase