Crystallization and Preliminary X-Ray Crystallographic Analysis of Carboxylesterase from Pseudomonas fluorescens

Large crystals of carboxylesterase from Pseudomonas fluorescens have been grown in the presence of dioxane using ammonium sulfate and lithium sulfate as precipitant. They belong to the tetragonal space group P41212 (or P43212), with unit cell dimensions of a = 82.01 (±0.06) Å and c = 145.44 (±0.08) Å. The presence of one carboxylesterase dimer in the asymmetric unit gives the crystal volume per protein mass (VM) of 2.56 Å3/Da and solvent fraction of 52.0% by volume. The crystals diffract to at least 2.3 Å Bragg spacing when exposed to CuKα X rays from a rotating anode generator. X-ray data (nearly complete to 2.6 Å Bragg spacing) have been collected from a native crystal.