1.3.1.42 - 390778 1.3.1.42 10 mg/ml purified recombinant isozyme OPR3 in 100 mM MES, pH 6.0, 100 mM NaCl, 0.3 mM TCEP, hanging drop vapour diffusion method, 0.002 ml protein solution with equal volume of well solution containing 8.75-10.0% monomethyl ether polyethylene glycol 5000, 0.1 M triethanolamine, pH 8.0, 0.275-0.35 M glycine, crystals are harvested into a cryoprotectant solution containing 12% monomethyl ether polyethylene glycol 5000, 0.1 M triethanolamine, pH 8.0, 0.4 M glycine, and 25% PEG 400, X-ray diffraction structure determination and analysis at 2.0 A resolution, molecular replacement 657324 1.3.1.42 at 2.0 A resolution, determination of the crystal structures of OPR3 in complex with the ligand p-hydroxybenzaldehyde, structural comparison with the OPR1:(9R,13R)-12-oxophytodienoate complex and further biochemical and mutational analyses reveals that 2 active-site residues, Phe74 and His244 in OPR3 are critical for substrate filtering 699588 1.3.1.42 crystal structure of Arabidopsis thaliana OPR3 in complex with 8-iso prostaglandin A1 (8-iso PGA1) is reported. The crystal structure is solved to 2.6 A. The positioning of 8-iso PGA1 reveals a new binding orientation for substrate in the active site that likely contributes to the relaxed stereospecificity observed for AtOPR3 relative to other OPR's 726461 1.3.1.42 native enzyme and mutants E291L and Y364F. Wild-type enzyme crystallizes as an extraordinary self-inhibiting dimer, dimerization is actively driven by the mutual binding of the two L6 loops into the two active sites 676813 1.3.1.42 one enzyme monomer per asymmetric unit, space group C2221. Enzyme is a member of an alpha/beta barrel fold family of FMN-containing oxidoreductases 677040 1.3.1.42 OPR1 390780 1.3.1.42 OPR1:p-hydroxybenzaldehyde complex at 2.3 A resolution, determination of the crystal structures of OPR1 in complex with the ligand p-hydroxybenzaldehyde, structural comparison with the OPR1:(9R,13R)-12-oxophytodienoate complex and further biochemical and mutational analyses reveals that 2 active-site residues, Tyr78 and Tyr246 in OPR1 are critical for substrate filtering 699588