Open AccessPreliminary crystallographic analysis of salicylate 1,2‐dioxygenase from Pseudaminobacter salicylatoxidans
Author(s) -
Matera I.,
Ferraroni M.,
Bürger S.,
Stolz A.,
Briganti F.
Publication year - 2006
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309106016435
Subject(s) - dioxygenase , tetragonal crystal system , chemistry , crystal structure , catalysis , ring (chemistry) , stereochemistry , crystallography , enzyme , biochemistry , organic chemistry
Salicylate 1,2‐dioxygenase, a new ring‐fission dioxygenase from the naphthalenesulfonate‐degrading strain Pseudaminobacter salicylatoxidans which oxidizes salicylate to 2‐oxohepta‐3,5‐dienedioic acid by a novel ring‐fission mechanism, has been crystallized. Diffraction‐quality crystals of salicylate 1,2‐dioxygenase were obtained using the sitting‐drop vapour‐diffusion method at 277 K from a solution containing 10%( w / v ) ethanol, 6%( w / v ) PEG 400, 0.1 M sodium acetate pH 4.6. Crystals belong to the primitive tetragonal space group P 4 3 2 1 2 or P 4 1 2 1 2, with unit‐cell parameters a = 133.3, c = 191.51 Å. A complete data set at 100 K extending to a maximum resolution of 2.9 Å was collected at a wavelength of 0.8423 Å. Molecular replacement using the coordinates of known extradiol dioxygenases structures as a model has so far failed to provide a solution for salicylate 1,2‐dioxygenase. Attempts are currently being made to solve the structure of the enzyme by MAD experiments using the anomalous signal of the catalytic Fe II ions. The salicylate 1,2‐dioxygenase structural model will assist in the elucidation of the catalytic mechanism of this ring‐fission dioxygenase from P. salicylatoxidans , which differs markedly from the known gentisate 1,2‐dioxygenases or 1‐hydroxy‐2‐naphthoate dioxygenases because of its unique ability to oxidatively cleave salicylate, gentisate and 1‐hydroxy‐2‐naphthoate with high catalytic efficiency.