title: High-resolution (1.5 A) crystal structure of phospholipase C from Bacillus cereus.
abstract: Both the phosphatidylinositol-hydrolysing and the phosphatidylcholine-hydrolysing phospholipases C have been implicated in the generation of second messengers in mammalian cells. The phosphatidylcholine-hydrolysing phospholipase C (PLC) from Bacillus cereus, a monomeric protein containing 245 amino-acid residues, is similar to some of the corresponding mammalian proteins. This, together with the fact that the bacterial enzyme can mimic the action of mammalian PLC in causing, for example, enhanced prostaglandin biosynthesis, suggests that B. cereus PLC can be used as a model for the hitherto poorly characterized mammalian PLCs. We report here the three-dimensional structure of B. cereus PLC at 1.5 A resolution. The enzyme is an all-helix protein belonging to a novel structural class and contains, at least in the crystalline state, three Zn2+ in the active site. We also present preliminary results from a study at 1.9 A resolution of the complex between PLC and inorganic phosphate (Pi) which indicate that the substrate binds directly to the metal ions.
authors.affiliation: Department of Chemistry, University of Tromsø, Norway.
authors.forename: E
authors.initials: E
authors.lastname: Hough
authors.forename: L K
authors.initials: LK
authors.lastname: Hansen
authors.forename: B
authors.initials: B
authors.lastname: Birknes
authors.forename: K
authors.initials: K
authors.lastname: Jynge
authors.forename: S
authors.initials: S
authors.lastname: Hansen
authors.forename: A
authors.initials: A
authors.lastname: Hordvik
authors.forename: C
authors.initials: C
authors.lastname: Little
authors.forename: E
authors.initials: E
authors.lastname: Dodson
authors.forename: Z
authors.initials: Z
authors.lastname: Derewenda
mesh_terms: D001409:Bacillus cereus; D001665:Binding Sites; D003460:Crystallization; D008958:Models, Molecular; D008968:Molecular Conformation; D015394:Molecular Structure; D010710:Phosphates / Q000378:metabolism; D010738:Type C Phospholipases / Q000378:metabolism
chemical_list: D010710:Phosphates; D010738:Type C Phospholipases