title: Three-dimensional structure of cholera toxin penetrating a lipid membrane.
abstract: Two-dimensional crystals of cholera toxin bound to receptors in a lipid membrane give diffraction extending to 15 A resolution. Three-dimensional structure determination reveals a ring of five B subunits on the membrane surface, with one-third of the A subunit occupying the center of the ring. The remaining mass of the A subunit appears to penetrate the hydrophobic interior of the membrane. Cleavage of a disulfide bond in the A subunit, which activates the toxin, causes a major conformational change, with the A subunit mostly exiting from the B ring.
authors.affiliation: Department of Cell Biology, Howard Hughes Medical Institute, Stanford University School of Medicine, CA 94305.
authors.forename: H O
authors.initials: HO
authors.lastname: Ribi
authors.forename: D S
authors.initials: DS
authors.lastname: Ludwig
authors.forename: K L
authors.initials: KL
authors.lastname: Mercer
authors.forename: G K
authors.initials: GK
authors.lastname: Schoolnik
authors.forename: R D
authors.initials: RD
authors.lastname: Kornberg
mesh_terms: D002772:Cholera Toxin; D005677:G(M1) Ganglioside; D008081:Liposomes; D046911:Macromolecular Substances; D008854:Microscopy, Electron; D008958:Models, Molecular; D010714:Phosphatidylethanolamines; D011487:Protein Conformation
chemical_list: D008081:Liposomes; D046911:Macromolecular Substances; D010714:Phosphatidylethanolamines; D005677:G(M1) Ganglioside; C020888:1,2-dielaidoylphosphatidylethanolamine; D002772:Cholera Toxin