Crystals of beta-xylanase from Aspergillus oryzae.

An endo-xylanase was isolated from the culture of fungus Aspergillus oryzae variant D5. The purified enzyme had a molecular weight of 24,000 and the isoelectric point of 3.6. Xylanase crystals were obtained from a polyethylene glycol 6000 solution by the hanging-drop method. Seeding was used for the enlargement of the crystal size. Crystals belong to the monoclinic space group P2(1) with cell dimensions a = 54.9 A, b = 74.5 A, c = 50.8 A, and beta = 108.7 degrees. Crystals diffract beyond 2.5 A resolution.