title: Crystal structure, at 2.6-A resolution, of the Streptomyces lividans xylanase A, a member of the F family of beta-1,4-D-glycanases.
abstract: The crystal structure of the 32-kDa catalytic domain of the Streptomyces lividans xylanase A was solved by molecular isomorphous replacement methods and subsequently refined at 2.6-A resolution to a conventional crystallographic R factor of 0.21. This is the first successful structure determination of a member of the F family of endo-beta-1,4-D-glycanases. Unlike the recently determined xylanases of the G family (Wakarchuk, W. W., Campbell, R. L., Sung, W. L., Davoodi, J., and Yaguchi, M. (1994) Protein Sci. 3, 467-475), where the catalytic domains have a unique beta-sheet structure, the 32-kDa domain of the S. lividans xylanase A is folded into a complete (alpha/beta)8 barrel, the first such fold observed among beta-1,4-D-glycanases. The active site is located at the carbonyl end of the beta barrel. The crystal structure supports the earlier assignment of Glu-128 and Glu-236 as the catalytic amino acids (Moreau, A., Roberge, M., Manin, C., Shareck, F., Kluepfel, D., and Morosoli, R. (1994) Biochem. J., in press).
authors.affiliation: Department of Biochemistry, University of Alberta, Edmonton, Canada.
authors.forename: U
authors.initials: U
authors.lastname: Derewenda
authors.forename: L
authors.initials: L
authors.lastname: Swenson
authors.forename: R
authors.initials: R
authors.lastname: Green
authors.forename: Y
authors.initials: Y
authors.lastname: Wei
authors.forename: R
authors.initials: R
authors.lastname: Morosoli
authors.forename: F
authors.initials: F
authors.lastname: Shareck
authors.forename: D
authors.initials: D
authors.lastname: Kluepfel
authors.forename: Z S
authors.initials: ZS
authors.lastname: Derewenda
mesh_terms: D001665:Binding Sites; D002480:Cellulase / Q000737:chemistry*; D018360:Crystallography, X-Ray; D043364:Endo-1,4-beta Xylanases; D006026:Glycoside Hydrolases / Q000737:chemistry*; D008969:Molecular Sequence Data; D011487:Protein Conformation; D013302:Streptomyces / Q000201:enzymology*
chemical_list: D006026:Glycoside Hydrolases; D002480:Cellulase; D043364:Endo-1,4-beta Xylanases