Crystallization and preliminary X-ray crystallographic analysis of enoyl-acyl carrier protein reductase from Helicobacter pylori

Enoyl-acyl carrier protein reductase (ENR) catalyzes the NADH-dependent stereospecific reduction of α,β-unsaturated fatty acids bound to the acyl-carrier protein. ENR from Helicobacter pylori has been overexpressed in Escherichia coli and has been crystallized in the presence of its cofactor NADH and the inhibitor triclosan (or its analogue diclosan) at 296 K using polyethylene glycol (PEG) 400 as a precipitant. For the triclosan (or diclosan) complex, diffraction data to 2.5 (or 2.3) Å resolution have been collected using synchrotron X-­rays. The crystals belong to the monoclinic space group P2₁, with unit-cell parameters a = 73.35, b = 94.91, c = 75.38 Å, β = 106.21° for the triclosan complex (or a = 73.25, b = 95.07, c = 75.02 Å, β = 106.53° for the diclosan complex). The asymmetric unit contains one homotetramer, with a corresponding V_M of 2.10 ų Da⁻¹ and a solvent content of 41% by volume.