Crystallization and preliminary X-ray diffraction studies of La1 from Liocheles australasiae

A novel scorpion venom peptide, La1 from Liocheles australasiae, with a molecular weight of 7.8 kDa, is presumed to possess a single von Willebrand factor type C (VWC) domain, a common protein module, based on the position of eight Cys residues in its sequence. The biological function of La1 is still unknown. Deciphering its three-dimensional structure will be helpful in understanding its biological function. La1 was crystallized by the sitting-drop vapour-diffusion method using magnesium sulfate as a precipitant. The crystals belonged to the monoclinic space group C2, with unit-cell parameters a = 63.0, b = 30.2, c = 32.3 angstrom, beta = 108.5 degrees, and diffracted to 1.9 angstrom resolution. The calculated V-M based on one molecule per asymmetric unit was 1.87 angstrom(3) Da(-1). The solvent content was 34.1%.