title: Crystallization and preliminary X-ray analysis of the apo form of Escherichia coli tryptophanase.
abstract: Tryptophanase from Escherichia coli is a pyridoxal phosphate-dependent homotetrametic enzyme with a subunit weight of 52 kDa. It has been crystallized in the apo form by the hanging-drop vapour-diffusion method using polyethylene glycol 400 as a precipitant and magnesium chloride as an additive. The crystals belong to the orthorhombic space group F222, with unit-cell parameters a = 118.4, b = 120.1, c = 171.2 A. A 97.8% complete data set to 1.9 A resolution was collected at a rotating-anode source from a single frozen crystal. Packing-density considerations agree with a monomer in the asymmetric unit with a solvent content of 55%. Tryptophanase mutants W330F and Y74F were crystallized under the same conditions and the crystals diffracted to a resolution limit of 1.9 A. Data sets of wild-type crystals soaked with L-tryptophan or pyridoxal phosphate were collected, as well as of Y74F mutant soaked with both.
authors.affiliation: Department of Chemistry, Ben-Gurion University of the Negev, POB 653, Beer-Sheva 84105, Israel.
authors.forename: Anna
authors.initials: A
authors.lastname: Kogan
authors.forename: Garik Y
authors.initials: GY
authors.lastname: Gdalevsky
authors.forename: Rivka
authors.initials: R
authors.lastname: Cohen-Luria
authors.forename: Abraham H
authors.initials: AH
authors.lastname: Parola
authors.forename: Yehuda
authors.initials: Y
authors.lastname: Goldgur
mesh_terms: D001051:Apoenzymes / Q000737:chemistry / Q000235:genetics; D003460:Crystallization; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D009154:Mutation / Q000235:genetics; D014364:Tryptophan / Q000235:genetics; D014368:Tryptophanase / Q000737:chemistry* / Q000235:genetics; D014443:Tyrosine / Q000235:genetics
chemical_list: D001051:Apoenzymes; D014443:Tyrosine; D014364:Tryptophan; D014368:Tryptophanase