Open AccessA preliminary neutron diffraction study of rasburicase, a recombinant urate oxidase enzyme, complexed with 8‐azaxanthin
Author(s) -
BudayovaSpano Monika,
Bonneté Françoise,
Ferté Natalie,
El Hajji Mohamed,
Meilleur Flora,
Blakeley Matthew Paul,
Castro Bertrand
Publication year - 2006
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309106006439
Subject(s) - neutron diffraction , protein crystallization , crystallography , chemistry , rasburicase , crystallization , materials science , crystal structure , uric acid , biochemistry , organic chemistry , hyperuricemia
Crystallization and preliminary neutron diffraction measurements of rasburicase, a recombinant urate oxidase enzyme expressed by a genetically modified Saccharomyces cerevisiae strain, complexed with a purine‐type inhibitor (8‐azaxanthin) are reported. Neutron Laue diffraction data were collected to 2.1 Å resolution using the LADI instrument from a crystal (grown in D 2 O) with volume 1.8 mm 3 . The aim of this neutron diffraction study is to determine the protonation states of the inhibitor and residues within the active site. This will lead to improved comprehension of the enzymatic mechanism of this important enzyme, which is used as a protein drug to reduce toxic uric acid accumulation during chemotherapy. This paper illustrates the high quality of the neutron diffraction data collected, which are suitable for high‐resolution structural analysis. In comparison with other neutron protein crystallography studies to date in which a hydrogenated protein has been used, the volume of the crystal was relatively small and yet the data still extend to high resolution. Furthermore, urate oxidase has one of the largest primitive unit‐cell volumes (space group I 222, unit‐cell parameters a = 80, b = 96, c = 106 Å) and molecular weights (135 kDa for the homotetramer) so far successfully studied with neutrons.