title: Two-dimensional crystallization experiments.
abstract: Our experience in the growth of two-dimensional crystals of different proteins is presented. Polyethylene glycol was used to produce two-dimensional arrays of haemocyanin from O. vulgaris and of cholera toxin. The arrays showed a hexagonal close-packed structure of only randomly oriented molecules. The increase in protein concentration probably occurred too quickly to allow complete crystallization. Different two-dimensional arrays of hexameric haemocyanin molecules (from P. interruptus) were obtained by microdialysis through the specimen supporting film. A comparison was made with X-ray data. Two-dimensional tetrameric arrays of molecules, possibly rhodopsin, were seen in samples of bovine retinal rod outer segments in the presence of ammonium sulphate. Two-dimensional crystals of complex I (from bovine mitochondria) were prepared by dialysis in the presence of ammonium sulphate. A three-dimensional reconstruction was made from two tilt-series by computer filtration using the direct SIRT procedure. Finally, the possibility of computer crystallization using correlation techniques in combination with correspondence analysis is discussed.
authors.forename: E F
authors.initials: EF
authors.lastname: van Bruggen
authors.forename: J F
authors.initials: JF
authors.lastname: van Breemen
authors.forename: W
authors.initials: W
authors.lastname: Keegstra
authors.forename: E J
authors.initials: EJ
authors.lastname: Boekema
authors.forename: M G
authors.initials: MG
authors.lastname: van Heel
mesh_terms: D000645:Ammonium Sulfate; D000818:Animals; D002417:Cattle; D002772:Cholera Toxin; D003201:Computers; D003460:Crystallization; D003461:Crystallography; D006433:Hemocyanins; D046911:Macromolecular Substances; D008565:Membrane Proteins; D008854:Microscopy, Electron; D008928:Mitochondria / Q000201:enzymology / Q000648:ultrastructure; D008958:Models, Molecular; D016660:NAD(P)H Dehydrogenase (Quinone); D008121:Nephropidae; D049831:Octopodiformes; D011092:Polyethylene Glycols; D011808:Quinone Reductases; D012168:Retinal Pigments; D012243:Rhodopsin; D012374:Rod Cell Outer Segment / Q000648:ultrastructure
chemical_list: D046911:Macromolecular Substances; D008565:Membrane Proteins; D012168:Retinal Pigments; D011092:Polyethylene Glycols; D012243:Rhodopsin; D002772:Cholera Toxin; D006433:Hemocyanins; C041831:NADH dehydrogenase (quinone); D016660:NAD(P)H Dehydrogenase (Quinone); D011808:Quinone Reductases; D000645:Ammonium Sulfate