Crystallization and preliminary X-ray diffraction analysis of membrane-bound respiratory [NiFe] hydrogenase from Hydrogenovibrio marinus.

Membrane-bound respiratory [NiFe] hydrogenase is an H2-uptake enzyme found in the periplasmic space of bacteria that plays a crucial role in energy-conservation processes. The heterodimeric unit of the enzyme from Hydrogenovibrio marinus was purified to homogeneity using chromatographic procedures. Crystals were grown using the sitting-drop vapour-diffusion method at room temperature. Preliminary crystallographic analysis revealed that the crystals belonged to space group P2(1), with unit-cell parameters a=75.72, b=116.59, c=113.40 Å, β=91.3°, indicating that two heterodimers were present in the asymmetric unit.