Analyzing the Substrate Specificity of a Class of Long-Horned-Beetle-Derived Xylanases by Using Synthetic Arabinoxylan Oligo- and Polysaccharides.
Chembiochem
; 21(10): 1517-1525, 2020 05 15.
Article
em En
| MEDLINE
| ID: mdl-31850611
ABSTRACT
Xylophagous long-horned beetles thrive in challenging environments. To access nutrients, they secrete plant-cell-wall-degrading enzymes in their gut fluid; among them are cellulases of the subfamilyâ
2 of glycoside hydrolase familyâ
5 (GH5_2). Recently, we discovered that several beetle-derived GH5_2s use xylan as a substrate instead of cellulose, which is unusual for this family of enzymes. Here, we analyze the substrate specificity of a GH5_2 xylanase from the beetle Apriona japonica (AJAGH5_2-1) using commercially available substrates and synthetic arabinoxylan oligo- and polysaccharides. We demonstrate that AJAGH5_2-1 processes arabinoxylan polysaccharides in a manner distinct from classical xylanase families such as GH10 and GH11. AJAGH5_2-1 is active on long oligosaccharides and cleaves at the non-reducing end of a substituted xylose residue (position +1) only if 1)â
three xylose residues are present upstream and downstream of the cleavage site, and 2)â
xylose residues at positions -1, -2, +2 and +3 are not substituted.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oligossacarídeos
/
Polissacarídeos
/
Besouros
/
Xilanos
/
Parede Celular
/
Endo-1,4-beta-Xilanases
Limite:
Animals
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article