title: Purification, crystallization and preliminary X-ray analysis of an unusual thioredoxin from the gastric pathogen Helicobacter pylori.
abstract: Thioredoxin-2 (HP1458) from Helicobacter pylori is a member of the thioredoxin family, but possesses the unusual active-site motif CPDC (compared with CGPC in other thioredoxins). H. pylori is deficient in the glutaredoxin system, making the thioredoxin system the sole reduction system in the bacterium and critical for its ability to survive oxidative stress. The recombinant protein has been overexpressed, purified and crystallized. This is the first reported crystallization of a thioredoxin possessing this unusual active site. Single crystals have been obtained using the sitting-drop technique. Crystals diffract to 2.4 A resolution and belong to space group P4(1), with unit-cell parameters a = b = 40.21, c = 64.65 A. Molecular replacement using AMoRe proved unsuccessful; however, implementation of the program BEAST gave successful molecular-replacement solutions.
authors.affiliation: Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5C9, Canada.
authors.forename: Heather
authors.initials: H
authors.lastname: Filson
authors.forename: Aine
authors.initials: A
authors.lastname: Fox
authors.forename: Dermot
authors.initials: D
authors.lastname: Kelleher
authors.forename: Henry J
authors.initials: HJ
authors.lastname: Windle
authors.forename: David A R
authors.initials: DA
authors.lastname: Sanders
mesh_terms: D020816:Amino Acid Motifs; D001665:Binding Sites; D003460:Crystallization / Q000379:methods; D016480:Helicobacter pylori / Q000737:chemistry*; D011994:Recombinant Proteins; D013879:Thioredoxins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D014961:X-Ray Diffraction / Q000379:methods
chemical_list: D011994:Recombinant Proteins; D013879:Thioredoxins