Purification, crystallization and X-ray diffraction study of extracellular dermal glycoprotein from carrot and the inhibition complex that it forms with an endo-β-glucanase from Aspergillus aculeatus

Extracellular dermal glycoprotein (EDGP) may play an important role in the plant defence system of the carrot (Daucus carota) as it has inhibitory activity against endo-beta-glucanase produced by invading pathogens. Here, EDGP and the inhibition complex that it forms with FI-CMCase, a carboxyl methyl cellulase from Aspergillus aculeatus, were successfully crystallized. The hexagonal crystal of EDGP belonged to space group P6(2), with unit-cell parameters a = b = 130.4, c = 44.5 angstrom, gamma = 120 degrees. The monoclinic crystal of the complex of EDGP with FI-CMCase belonged to space group C2, with unit-cell parameters a = 169.5, b = 143.0, c = 63.0 angstrom, beta = 110.9 degrees.