Alpha-L-arabinofuranosidase catalyses the hydrolysis of the alpha-1,2-, alpha-1,3-, and alpha-1,5-L-arabinofuranosidic bonds in L-arabinose-containing hemicelluloses such as arabinoxylan. AkAbf54 (the glycoside hydrolase family 54 alpha-L-arabinofuranosidase from Aspergillus kawachii) consists of two domains, a catalytic and an arabinose-binding domain. The latter has been named AkCBM42 [family 42 CBM (carbohydrate-binding module) of AkAbf54] because homologous domains are classified into CBM family 42.
View Article and Find Full Text PDFA role for N-linked oligosaccharides on the biochemical properties of recombinant alpha-l-arabinofuranosidase 54 (AkAbf54) defined in glycoside hydrolase family 54 from Aspergillus kawachii expressed in Pichia pastoris was analyzed by site-directed mutagenesis. Two N-linked glycosylation motifs (Asn(83)-Thr-Thr and Asn(202)-Ser-Thr) were found in the AkAbf54 sequence. AkAbf54 comprises two domains, a catalytic domain and an arabinose-binding domain classified as carbohydrate-binding module 42.
View Article and Find Full Text PDFWe screened 20,000 clones of an expressed sequence tag (EST) library from Aspergillus oryzae (http://www.nrib.go.
View Article and Find Full Text PDFWe engineered an acetyl xylan esterase (AwaxeA) gene from Aspergillus awamori into a heterologous expression system in Pichia pastoris. Purified recombinant AwAXEA (rAwAXEA) displayed the greatest hydrolytic activity toward alpha-naphthylacetate (C2), lower activity toward alpha-naphthylpropionate (C3) and no detectable activity toward acyl-chain substrates containing four or more carbon atoms. Putative catalytic residues, Ser(119), Ser(146), Asp(168) and Asp(202), were substituted for alanine by site-directed mutagenesis.
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