High-level expression and enzymatic properties of a novel thermostable xylanase with high arabinoxylan degradation ability from Chaetomium sp. suitable for beer mashing.
Int J Biol Macromol
; 168: 223-232, 2021 Jan 31.
Article
em En
| MEDLINE
| ID: mdl-33309660
ABSTRACT
A novel thermostable xylanase gene from Chaetomium sp. CQ31 was cloned and codon-optimized (CsXynBop). The deduced protein sequence of the gene shared the highest similarity of 75% with the glycoside hydrolase (GH) family 10 xylanase from Achaetomium sp. Xz-8. CsXynBop was over-expressed in Pichia pastoris GS115 by high-cell density fermentation, with the highest xylanase yield of 10,017 U/mL. The recombinant xylanase (CsXynBop) was purified to homogeneity and biochemically characterized. CsXynBop was optimally active at pH 6.5 and 85 °C, respectively, and stable over a broad pH range of 5.0-9.5 and up to 60 °C. The enzyme exhibited strict substrate specificity towards oat-spelt xylan (2, 489 U/mg), beechwood xylan (1522 U/mg), birchwood xylan (1067 U/mg), and showed relatively high activity towards arabinoxylan (1208 U/mg), but exhibited no activity on other tested polysaccharides. CsXynBop hydrolyzed different xylans to yield mainly xylooligosaccharides (XOSs) with degree of polymerization (DP) 2-5. The application of CsXynBop (200 U/g malt) in malt mashing substantially decreased the filtration time and viscosity of malt by 42.3% and 8.6%, respectively. These excellent characteristics of CsXynBop may make it a good candidate in beer industry.
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Texto completo:
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Chaetomium
/
Endo-1,4-beta-Xilanases
Idioma:
En
Revista:
Int J Biol Macromol
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
China