Crystals of family 11 xylanase II from Trichoderma longibrachiatum that diffract to atomic resolution.

Xylanases catalyse the cleavage of various forms of xylan. A new crystal form of xylanase II from the fungus Trichoderma longibrachiatum that diffracts to better than 1 A resolution was grown from 12% PEG 8K, 0.1 M Tris pH 8.5, 0.2 M CaCl(2) with the addition of 2% glycerol to overcome crystal twinning. The crystals grow in a body-centered orthorhombic Bravais lattice, with unit-cell parameters a = 66.78, b = 67.94, c = 79.18 A. The solvent content is 42% with one molecule per asymmetric unit. Molecular-replacement analysis reveals the space group to be I222. This atomic resolution structure will provide important insights that will lead to a better understanding of the enzymatic mechanism of the family 11 xylanases.