title: Crystallization of dihydrodipicolinate synthase from a clinical isolate of Streptococcus pneumoniae.
abstract: Dihydrodipicolinate synthase (DHDPS; EC 4.2.1.52) catalyzes the rate-limiting step in the (S)-lysine biosynthesis pathway of bacteria and plants. Here, the cloning of the DHDPS gene from a clinical isolate of Streptococcus pneumoniae (OXC141 strain) and the strategy used to express, purify and crystallize the recombinant enzyme are described. Diffracting crystals were grown in high-molecular-weight PEG precipitants using the hanging-drop vapour-diffusion method. The best crystal, from which data were collected, diffracted to beyond 2.0 A resolution. Initially, the crystals were thought to belong to space group P4(2)2(1)2, with unit-cell parameters a = 105.5, b = 105.5, c = 62.4 A. However, the R factors remained high following initial processing of the data. It was subsequently shown that the data set was twinned and it was thus reprocessed in space group P2, resulting in a significant reduction in the R factors. Determination of the structure will provide insight into the design of novel antimicrobial agents targeting this important enzyme from S. pneumoniae.
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria 3010, Australia.
authors.forename: Natalia E
authors.initials: NE
authors.lastname: Sibarani
authors.forename: Michael A
authors.initials: MA
authors.lastname: Gorman
authors.forename: Con
authors.initials: C
authors.lastname: Dogovski
authors.forename: Michael W
authors.initials: MW
authors.lastname: Parker
authors.forename: Matthew A
authors.initials: MA
authors.lastname: Perugini
mesh_terms: D003001:Cloning, Molecular; D003460:Crystallization; D018360:Crystallography, X-Ray; D006836:Hydro-Lyases / Q000737:chemistry*; D013296:Streptococcus pneumoniae / Q000201:enzymology
chemical_list: D006836:Hydro-Lyases; C020040:4-hydroxy-tetrahydrodipicolinate synthase