Crystallization and preliminary X-ray analysis of enoyl-acyl carrier protein reductase (FabK) from Streptococcus pneumoniae.

The enoyl-acyl carrier protein (ACP) reductase from Streptococcus pneumoniae (FabK; EC 1.3.1.9) is responsible for catalyzing the final step in each elongation cycle of fatty-acid biosynthesis. Selenomethionine-substituted FabK was purified and crystallized by the hanging-drop vapour-diffusion method at 277 K. The crystal belongs to space group P2(1), with unit-cell parameters a = 50.26, b = 126.70, c = 53.63 A, beta = 112.46 degrees . Diffraction data were collected to 2.00 A resolution using synchrotron beamline BL32B2 at SPring-8. Two molecules were estimated to be present in the asymmetric unit, with a solvent content of 45.1%.