title: Structure of xylanase Xys1delta from Streptomyces halstedii.
abstract: Xylanases hydrolyze the beta-1,4-linked xylose backbone of xylans. They are of increasing interest in the paper and food industries for their pre-bleaching and bio-pulping applications. Such industries demand new xylanases to cover a wider range of cleavage specificity, activity and stability. The catalytic domain of xylanase Xys1 from Streptomyces halstedii JM8 was expressed, purified and crystallized and native data were collected to 1.78 A resolution with an R(merge) of 4.4%. The crystals belong to space group P2(1)2(1)2(1), with unit-cell parameters a = 34.05, b = 79.60, c = 87.80 A. The structure was solved by the molecular-replacement method using the structure of the homologue Xyl10A from Streptomyces lividans. In a similar manner to other members of its family, Xys1 folds to form a standard (beta/alpha)(8) barrel with the two catalytic functions, the acid/base and the nucleophile, at its C-terminal side. The overall structure is described and compared with those of related xylanases.
authors.affiliation: Institut de Biologia Molecular de Barcelona, Consejo Superior de Investigaciones Científicas, Jordi Girona 18-26, 08034 Barcelona, Spain. acpcri@ibmb.csic.es
authors.forename: Albert
authors.initials: A
authors.lastname: Canals
authors.forename: M Cristina
authors.initials: MC
authors.lastname: Vega
authors.forename: F Xavier
authors.initials: FX
authors.lastname: Gomis-Rüth
authors.forename: Margarita
authors.initials: M
authors.lastname: Díaz
authors.forename: Ram óN I
authors.initials: Ró
authors.lastname: Santamaría R
authors.forename: Miquel
authors.initials: M
authors.lastname: Coll
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry*; D020134:Catalytic Domain; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D011487:Protein Conformation; D017510:Protein Folding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D013302:Streptomyces / Q000201:enzymology*; D014995:Xylosidases / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D014995:Xylosidases; C107879:Xys1 protein, Streptomyces halstedii