   1.3.7.4 | purified recombinant wild-type and selenomethionine-labeled phytochromobilin synthase in complex with substrate biliverdin IXalpha, sitting drop vapor diffusion method, mixing of protein in 150 mM KCl, and 20 mM Tris-HCl, pH 7.4, with reservoir solution, at 4°C. Tiny needle-shaped crystals of the BV-PPhiB synthase complex are obtained with a reservoir solution containing 20% w/v PEG 8000, 0.1 M Tris-HCl, pH 8.5, and 0.2 M MgCl2. Isomorphous crystals are also obtained with a reservoir solution containing 30% w/v PEG 4000, 0.1 M Tris-HCl, pH 8.5, and 0.2 M MgCl2, X-ray diffraction structure determination and analysis at 1.95-2.2 A resolution |
