crystals are grown using the sitting-drop, vapour-diffusion method. C2221 crystals are grown with 1.65 M ammonium sulfate, 5% PEG 400, 100 mM HepesNaOH (pH 7.5). The crystal structure is solved by multiwavelength anomalous diffraction phasing. The structure is refined at 1.30 A resolution. The core of D-hydantoinase consists of a (alpha/beta)(8)-barrel, which is flanked by a beta-sheet domain and some additional helices. In the active site, a carboxylated lysine residue and the catalytically active hydroxide ion bridge a binuclear zinc centre |
Thermus sp. |