title: Crystallization and preliminary X-ray crystallographic studies of SMU.134 protein from caries pathogen Streptococcus mutans.
abstract: The smu.134 gene encodes a putative transcriptional regulator of 217 residues in Streptococcus mutans, a major pathogen for human dental caries. The gene was cloned into expression vector pET28alpha and expressed in soluble form in E. coli strain BL21 (DE3) with a His tag at its N-terminus. The recombinant protein SMU.134 was purified to homogeneity in a two step procedure of Ni(2+ ) chelating and size exclusion chromatography. Crystals suitable for X-ray diffraction were obtained by hanging-drop vapor diffusion method and diffracted to 2.6 A;. The crystal belonged to space group P2(1)2(1)2(1), with unit-cell parameters a=55.03 A, b=80.84 A, c=107.96 A.
authors.affiliation: Institute for Nanobiomedical Technology and Membrane Biology, West China Hospital, Sichuan University, Chengdu 610065, Sichuan, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Li
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: D003001:Cloning, Molecular; D003460:Crystallization; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000378:metabolism; D013295:Streptococcus mutans / Q000737:chemistry*; D014157:Transcription Factors / Q000737:chemistry*
chemical_list: D014157:Transcription Factors