Purification and preliminary crystallographic analysis of a Penicillium expansum lipase

PF898 is a strain of Penicillium expansum optimized for the high level production of Penicillium expansum lipase (PEL). This PEL is unique compared with other lipases in several aspects, For example, the PEL shows low sequence identities (<30%) to all other known lipases, and high percentage of hydrophobic residues in the N-terminal region. The PEL was purified to homogeneity and shown to be 28 kDa by SDS-PAGE. Crystals suitable for X-ray diffraction analysis were obtained by the sitting-drop method of vapor diffusion with ammonia sulfate as the precipitating agent at 298 K. The crystals have tetragonal lattice and unit-cell parameters of a = b = 88.09 Å, c = 126.54 Å. Diffraction data were collected to a resolution of 2.08 Å on an in-house rotating-anode generator.