title: Protein preparation, crystallization and preliminary X-ray crystallographic analysis of SMU.961 protein from the caries pathogen Streptococcus mutans.
abstract: The smu.961 gene encodes a putative protein of 183 residues in Streptococcus mutans, a major pathogen in human dental caries. The gene was cloned into expression vector pET28a and expressed in a substantial quantity in Escherichia coli strain BL21 (DE3) with a His tag at its N-terminus. The recombinant protein SMU.961 was purified to homogeneity in a two-step procedure consisting of Ni2+-chelating and size-exclusion chromatography. Crystals suitable for X-ray diffraction were obtained by the hanging-drop vapour-diffusion method and diffracted to 2.9 A resolution at beamline I911-3, MAX-II-lab, Sweden. The crystal belonged to space group C2, with unit-cell parameters a = 98.62, b = 73.73, c = 184.73 A, beta = 98.82 degrees.
authors.affiliation: Institute for Nanobiomedical Technology and Membrane Biology, West China Hospital, Sichuan University, Chengdu 610065, Sichuan, People's Republic of China.
authors.forename: Xiong-Zhuo
authors.initials: XZ
authors.lastname: Gao
authors.forename: Lan-Fen
authors.initials: LF
authors.lastname: Li
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Su
authors.forename: XiaoJun
authors.initials: X
authors.lastname: Zhao
authors.forename: Yu-He
authors.initials: YH
authors.lastname: Liang
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry*; D018360:Crystallography, X-Ray; D003731:Dental Caries / Q000382:microbiology*; D006801:Humans; D011994:Recombinant Proteins / Q000032:analysis / Q000737:chemistry*; D013295:Streptococcus mutans / Q000737:chemistry* / Q000472:pathogenicity; D014961:X-Ray Diffraction
chemical_list: D001426:Bacterial Proteins; D011994:Recombinant Proteins