Crystallization and preliminary crystallographic analysis of GanB, a GH42 intracellular ß-galactosidase from Geobacillus stearothermophilus.
Acta Crystallogr Sect F Struct Biol Cryst Commun
; 69(Pt 10): 1114-9, 2013 Oct.
Article
em En
| MEDLINE
| ID: mdl-24100561
ABSTRACT
Geobacillus stearothermophilus T-6 is a Gram-positive thermophilic soil bacterium that contains a multi-enzyme system for the utilization of plant cell-wall polysaccharides, including xylan, arabinan and galactan. The bacterium uses a number of endo-acting extracellular enzymes that break down the high-molecular-weight polysaccharides into decorated oligosaccharides. These oligosaccharides enter the cell and are further hydrolyzed into sugar monomers by a set of intracellular glycoside hydrolases. One of these intracellular degrading enzymes is GanB, a glycoside hydrolase family 42 ß-galactosidase capable of hydrolyzing short ß-1,4-galactosaccharides to galactose. GanB and related enzymes therefore play an important part in the hemicellulolytic utilization system of many microorganisms which use plant biomass for growth. The interest in the biochemical characterization and structural analysis of these enzymes stems from their potential biotechnological applications. GanB from G. stearothermophilus T-6 has recently been cloned, overexpressed, purified, biochemically characterized and crystallized in our laboratory as part of its complete structure-function study. The best crystals obtained for this enzyme belong to the primitive orthorhombic space group P212121, with average crystallographic unit-cell parameters of a=71.84, b=181.35, c=196.57â
Å. Full diffraction data sets to 2.45 and 2.50â
Å resolution have been collected for both the wild-type enzyme and its E323A nucleophile catalytic mutant, respectively, as measured from flash-cooled crystals at 100â
K using synchrotron radiation. These data are currently being used for the full three-dimensional crystal structure determination of GanB.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Geobacillus stearothermophilus
/
Beta-Galactosidase
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Espaço Intracelular
Idioma:
En
Revista:
Acta Crystallogr Sect F Struct Biol Cryst Commun
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Israel