1.8.4.8 - 1.8.4.8 crystal structure at 2.0 A. The enzyme shows striking similarity to the structure of the ATP pyrophosphatase domain of GMP synthetase, indicating that both enzyme families have evolved from a common ancestral nucleotide-binding fold 1.8.4.8 crystal structure of Escherichia coli 3'-phosphoadenosine-5'-phosphosulfate reductase in complex with Escherichia coli thioredoxin 1 determined to 3.0 A resolution, crystals are grown by vapor diffusion in sitting drops