title: Overexpression, purification and crystallization of a choline-binding protein CbpI from Streptococcus pneumoniae.
abstract: The choline-binding protein CbpI from Streptococcus pneumoniae is a 23.4 kDa protein with no known function. The protein has been successfully purified initially using Ni-NTA chromatography and to homogeneity using Q-Sepharose ion-exchange resin as an affinity column. CbpI was crystallized using PEG 3350 as a precipitant and X-ray crystallographic analysis showed that the crystals belonged to the tetragonal space group P4, with unit-cell parameters a = b = 83.31, c = 80.29 angstroms, alpha = beta = gamma = 90 degrees. The crystal contains two molecules in the asymmetric unit with a solvent content of 55.7% (V(M) = 2.77 angstroms3 Da(-1)) and shows a diffraction limit of 3.5 angstroms.
authors.affiliation: Department of Chemistry and WestCHEM, Glasgow Biomedical Research Centre (GBRC), University of Glasgow, 120 University Place, Glasgow G12 8TA, Scotland. neison@chem.gla.ac.uk
authors.forename: Neil G
authors.initials: NG
authors.lastname: Paterson
authors.forename: Alan
authors.initials: A
authors.lastname: Riboldi-Tunicliffe
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Mitchell
authors.forename: Neil W
authors.initials: NW
authors.lastname: Isaacs
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D002852:Chromatography, Ion Exchange; D008958:Models, Molecular; D008970:Molecular Weight; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification; D013296:Streptococcus pneumoniae / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D011994:Recombinant Proteins