title: E. coli hemolysin E (HlyE, ClyA, SheA): X-ray crystal structure of the toxin and observation of membrane pores by electron microscopy.
abstract: Hemolysin E (HlyE) is a novel pore-forming toxin of Escherichia coli, Salmonella typhi, and Shigella flexneri. Here we report the X-ray crystal structure of the water-soluble form of E. coli HlyE at 2.0 A resolution and the visualization of the lipid-associated form of the toxin in projection at low resolution by electron microscopy. The crystal structure reveals HlyE to be the first member of a new family of toxin structures, consisting of an elaborated helical bundle some 100 A long. The electron micrographs show how HlyE oligomerizes in the presence of lipid to form transmembrane pores. Taken together, the data from these two structural techniques allow us to propose a simple model for the structure of the pore and for membrane interaction.
authors.affiliation: The Krebs Institute, Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, United Kingdom.
authors.forename: A J
authors.initials: AJ
authors.lastname: Wallace
authors.forename: T J
authors.initials: TJ
authors.lastname: Stillman
authors.forename: A
authors.initials: A
authors.lastname: Atkins
authors.forename: S J
authors.initials: SJ
authors.lastname: Jamieson
authors.forename: P A
authors.initials: PA
authors.lastname: Bullough
authors.forename: J
authors.initials: J
authors.lastname: Green
authors.forename: P J
authors.initials: PJ
authors.lastname: Artymiuk
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000648:ultrastructure; D001427:Bacterial Toxins / Q000737:chemistry*; D017124:Conserved Sequence; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000737:chemistry; D029968:Escherichia coli Proteins; D006460:Hemolysin Proteins / Q000737:chemistry* / Q000648:ultrastructure; D008055:Lipids / Q000737:chemistry; D008565:Membrane Proteins / Q000737:chemistry / Q000648:ultrastructure; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D018272:Porins / Q000737:chemistry* / Q000648:ultrastructure; D020836:Protein Structure, Quaternary; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012485:Salmonella typhi / Q000737:chemistry; D017386:Sequence Homology, Amino Acid; D012763:Shigella flexneri / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D029968:Escherichia coli Proteins; D006460:Hemolysin Proteins; C036507:Hlya protein, E coli; D008055:Lipids; D008565:Membrane Proteins; D018272:Porins; C119944:hlyE protein, E coli