title: Crystallization and preliminary X-ray diffraction studies on the DNA-binding domain of the transcriptional activator protein PhoB from Escherichia coli.
abstract: PhoB is a transcriptional factor that activates more than 30 genes of the pho regulon in response to phosphate starvation. Crystals of its C-terminal domain (PhoBC) were obtained in two forms. The first crystal form, obtained from phosphate solution, belongs to space group P2(1), with unit-cell parameters a = 30.7, b = 105.9, c = 30.9 A, beta = 110.3 degrees. The second form, crystallized from PEG solution, belongs to the same space group, but has a smaller unit cell (a = 30.6, b = 37.5, c = 44.4 A, beta = 109.4 degrees ). Crystals of selenomethionyl-derivatized PhoBC were obtained using the conditions for the second crystal form. Diffraction data from wild-type PhoBC (2.0 A resolution) and MAD data sets from selenomethionyl-derivative PhoBC (3.0 A resolution) have been collected at 100 K with a synchrotron-radiation source. MAD data analysis is in progress.
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification; D003460:Crystallization; D018360:Crystallography, X-Ray / Q000379:methods; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000302:isolation & purification; D004926:Escherichia coli / Q000737:chemistry*; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000302:isolation & purification; D011092:Polyethylene Glycols; D020033:Protein Isoforms / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D020033:Protein Isoforms; C061278:PhoB protein, Bacteria; D011092:Polyethylene Glycols