title: Overproduction, purification, crystallization and preliminary X-ray characterization of the family 46 carbohydrate-binding module (CBM46) of endo-β-1,4-glucanase B (CelB) from Bacillus halodurans.
abstract: Plant cell-wall polysaccharides offer an abundant energy source utilized by many microorganisms, thus playing a central role in carbon recycling. Aerobic microorganisms secrete carbohydrate-active enzymes (CAZymes) that catabolize this composite structure, comprising cellulose, hemicellulose and lignin, into simple compounds such as glucose. Carbohydrate-binding modules (CBMs) enhance the efficacy of associated CAZYmes. They are organized into families based on primary-sequence homology. CBM family 46 contains more than 40 different members, but has yet to be fully characterized. Here, a recombinant derivative of the C-terminal family 46 CBM module (BhCBM46) of Bacillus halodurans endo-β-1,4-glucanase B (CelB) was overexpressed in Escherichia coli and purified by immobilized metal-ion affinity chromatography. Preliminary structural characterization was carried out on BhCBM46 crystallized in different conditions. The crystals of BhCBM46 belonged to the tetragonal space group I4₁22. Data were collected for the native form and a selenomethionine derivative to 2.46 and 2.3 Å resolution, respectively. The BhCBM46 structure was determined by a single-wavelength anomalous dispersion experiment using AutoSol from the PHENIX suite.
authors.affiliation: CIISA-Faculdade de Medicina Veterinaria, Universidade de Lisboa, Avenida da Universidade Técnica, 1300-477 Lisbon, Portugal.
authors.forename: Immacolata
authors.initials: I
authors.lastname: Venditto
authors.affiliation: CIISA-Faculdade de Medicina Veterinaria, Universidade de Lisboa, Avenida da Universidade Técnica, 1300-477 Lisbon, Portugal.
authors.forename: Helena
authors.initials: H
authors.lastname: Santos
authors.affiliation: CIISA-Faculdade de Medicina Veterinaria, Universidade de Lisboa, Avenida da Universidade Técnica, 1300-477 Lisbon, Portugal.
authors.forename: Luís M A
authors.initials: LM
authors.lastname: Ferreira
authors.affiliation: Graduate School of Bioresources, Mie University, Tsu 514-8507, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Sakka
authors.affiliation: CIISA-Faculdade de Medicina Veterinaria, Universidade de Lisboa, Avenida da Universidade Técnica, 1300-477 Lisbon, Portugal.
authors.forename: Carlos M G A
authors.initials: CM
authors.lastname: Fontes
authors.affiliation: CIISA-Faculdade de Medicina Veterinaria, Universidade de Lisboa, Avenida da Universidade Técnica, 1300-477 Lisbon, Portugal.
authors.forename: Shabir
authors.initials: S
authors.lastname: Najmudin
mesh_terms: D001407:Bacillus / Q000201:enzymology*; D050260:Carbohydrate Metabolism; D002480:Cellulase / Q000737:chemistry / Q000378:metabolism*; D002846:Chromatography, Affinity; D003460:Crystallization; D018360:Crystallography, X-Ray; D004591:Electrophoresis, Polyacrylamide Gel; D011487:Protein Conformation
chemical_list: D002480:Cellulase
keywords: Bacillus halodurans; carbohydrate-binding module family 46; endo-β-1,4-glucanase