title: Small angle X-ray scattering study on bovine porphobilinogen synthase (5-aminolaevulinate dehydratase).
abstract: The quaternary structure of the native (zinc) porphobilinogen synthase (5-amino-laevulinate dehydratase) from bovine liver and its lead-substituted derivative is studied in solution by small angle X-ray scattering. In spite of the profound inhibitory effect of lead ions in the enzyme they do not produce a change in the quaternary structure detectable by small angle X-ray scattering. The most important molecular parameters of the native enzyme were found to be: radius of gyration Rg = 4.04 +/- 0.04 nm and maximum dimension Dmax = 12.0 +/- 0.5 nm. The corresponding values for the lead derivative are: Rg = 4.26 +/- 0.1 nm and Dmax = 12.5 +/- 0.5 nm. The quaternary structure of the enzyme in solution is described by a model, which fits the experimental scattering and distance distribution function.
authors.affiliation: Institut für Physikalische Chemie der Karl-Franzens-Universität, Graz, Austria.
authors.forename: I
authors.initials: I
authors.lastname: Pilz
authors.forename: E
authors.initials: E
authors.lastname: Schwarz
authors.forename: M
authors.initials: M
authors.lastname: Vuga
authors.forename: D
authors.initials: D
authors.lastname: Beyersmann
mesh_terms: D000818:Animals; D002417:Cattle; D008099:Liver / Q000201:enzymology; D046911:Macromolecular Substances; D008958:Models, Molecular; D000623:Porphobilinogen Synthase; D011487:Protein Conformation; D014961:X-Ray Diffraction
chemical_list: D046911:Macromolecular Substances; D000623:Porphobilinogen Synthase