Crystallization and preliminary neutron analysis of the dissimilatory sulfite reductase D (DsrD) protein from the sulfate-reducing bacterium

Chatake, Toshiyuki; Mizuno, Nobuhiro*; Voordown, G.*; Higuchi, Yoshiki*; Arai, Shigeki; Tanaka, Ichiro; Niimura, Nobuo

Issimilatory sulfite reductase D (DsrD) from has been crystallized for a neutron diffraction study. The initial crystals obtained were too small for the neutron experiment. In order to obtain a larger crystal (1 mm), a combination of two techniques was used to find the optimum crystallization conditions: a crystallization phase diagram, followed by crystal-quality assessment via X-ray diffraction. Using conditions determined in this manner, a large single crystal (1.7 mm) of the DsrD protein was subsequently grown in DO solution by the macro-seeding technique. The neutron diffraction experiment was carried out using the BIX-3 diffractometer at the Japan Atomic Energy Research Institute (JAERI), and the diffraction data up to 2.4 AA resolution could be collected from this crystal.