Constructing arabinofuranosidases for dual arabinoxylan debranching activity.
Biotechnol Bioeng
; 115(1): 41-49, 2018 Jan.
Article
em En
| MEDLINE
| ID: mdl-28868788
ABSTRACT
Enzymatic conversion of arabinoxylan requires α-L-arabinofuranosidases able to remove α-L-arabinofuranosyl residues (α-L-Araf) from both mono- and double-substituted D-xylopyranosyl residues (Xylp) in xylan (i.e., AXH-m and AXH-d activity). Herein, SthAbf62A (a family GH62 α-L-arabinofuranosidase with AXH-m activity) and BadAbf43A (a family GH43 α-L-arabinofuranosidase with AXH-d3 activity), were fused to create SthAbf62A_BadAbf43A and BadAbf43A_SthAbf62A. Both fusion enzymes displayed dual AXH-m,d and synergistic activity toward native, highly branched wheat arabinoxylan (WAX). When using a customized arabinoxylan substrate comprising mainly α-(1 â 3)-L-Araf and α-(1 â 2)-L-Araf substituents attached to disubstituted Xylp (d-2,3-WAX), the specific activity of the fusion enzymes was twice that of enzymes added as separate proteins. Moreover, the SthAbf62A_BadAbf43A fusion removed 83% of all α-L-Araf from WAX after a 20 hr treatment. 1 H NMR analyses further revealed differences in SthAbf62A_BadAbf43 rate of removal of specific α-L-Araf substituents from WAX, where 9.4 times higher activity was observed toward d-α-(1 â 3)-L-Araf compared to m-α-(1 â 3)-L-Araf positions.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Xilanos
/
Proteínas Recombinantes de Fusão
/
Glicosídeo Hidrolases
Idioma:
En
Revista:
Biotechnol Bioeng
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Canadá