   3.2.1.57 | for crystallization, the enzyme is treated with endoglycosidase Hf, by hanging drop vapor-diffusion method, unliganded and isopanose-complexed forms of IPU, both solved at 1.7 A resolution. Unliganded IPU belongs to space group P212121, which contains two molecules and 1273 water molecules in an asymmetric unit. IPU is composed of domains N and C joined by a short linker, with electron density maps for 11 or 12 N-acetylglucosamine residues per molecule. Domain N consists of 13 beta-strands and forms a beta-sandwich. Domain C, where the active site is located, forms a right-handed beta-helix. Overall conformation of IPU in complex with isopanose is essentially identical with that of unliganded IPU |
| 3.2.1.57 | purified deglycosylated recombinant enzyme mutant N448A complexed with substrate isopanose, hanging drop vapour diffusion method, 20°C, mixing of 0.001 ml protein in 10 mM sodium acetate, pH 3.5, with 0.001 ml of reservoir solution containing 10-13% w/w PEG 8000, and 50 mM sodium acetate, pH 4.5-5.0, cryoprotection with 20% v/v glycerol in reservoir solution, X-ray diffraction structure determination and analysis at 2.2 A resolution, molecular replacement method, the crystal belongs to the P21 space group and contains four molecules in the asymmetric unit, substrate binding structure, overview |
