Acta Crystallographica Section F

Structural Biology and Crystallization Communications

Volume 61, Part 12 (December 2005)

crystallization communications

Acta Cryst. (2005). F61, 1054-1057 [ doi:10.1107/S1744309105036262 ]

Crystallization and preliminary crystallographic analysis of a family 43 -D-xylosidase from Geobacillus stearothermophilus T-6

C. Brüx, K. Niefind, A. Ben-David, M. Leon, G. Shoham, Y. Shoham and D. Schomburg

Abstract: [beta] -D-Xylosidases (EC 3.2.1.37) are hemicellulases that cleave single xylose units from the nonreducing end of xylooligomers. In this study, the crystallization and preliminary X-ray analysis of a [beta] -D-xylosidase from Geobacillus stearothermophilus T-6 (XynB3), a family 43 glycoside hydrolase, is described. XynB3 is a 535-amino-acid protein with a calculated molecular weight of 61 891 Da. Purified recombinant native and catalytic inactive mutant proteins were crystallized and cocrystallized with xylobiose in two different space groups, P2₁2₁2 (unit-cell parameters a = 98.32, b = 99.36, c = 258.64 Å) and P4₁2₁2 (or the enantiomorphic space group P4₃2₁2; unit-cell parameters a = b = 140.15, c = 233.11 Å), depending on the detergent. Transferring crystals to cryoconditions required a very careful protocol. Orthorhombic crystals diffract to 2.5 Å and tetragonal crystals to 2.2 Å.

Keywords: family 43 glycosidase hydrolases; xylosidases; hemicellulases; Geobacillus stearothermophilus; xylan; xylose.