Send to

Choose Destination
Acta Crystallogr Sect F Struct Biol Cryst Commun. 2010 May 1;66(Pt 5):549-53. doi: 10.1107/S174430911001119X. Epub 2010 Apr 29.

A preliminary crystallographic study of recombinant NicX, an Fe(2+)-dependent 2,5-dihydroxypyridine dioxygenase from Pseudomonas putida KT2440.

Author information

Departamento de Biología Medioambiental, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain.


NicX from Pseudomonas putida KT2440 is an Fe(2+)-dependent dioxygenase that is involved in the aerobic degradation of nicotinic acid. The enzyme converts 2,5-dihydroxypyridine to N-formylmaleamic acid when overexpressed in Escherichia coli. Biophysical characterization of NicX by analytical gel-filtration chromatography revealed that it behaves as an oligomeric assembly in solution, with an apparent molecular weight that is consistent with a hexameric species. NicX was crystallized by the hanging-drop vapour-diffusion method at 291 K. Diffraction data were collected to a resolution of 2.0 A at the ESRF. The crystals most probably belong to the orthorhombic space group C222 or C222(1). The estimated Matthews coefficient was 2.4 A(3) Da(-1), corresponding to 50% solvent content, which is consistent with the presence of three protein molecules in the asymmetric unit. Analysis of the crystal data together with chromatographic results supports NicX being a hexameric assembly composed of two cyclic trimers. Currently, crystallization of recombinant selenomethionine-containing NicX is in progress.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for International Union of Crystallography Icon for PubMed Central
Loading ...
Support Center