Motif-guided identification of a glycoside hydrolase family 1 α-L-arabinofuranosidase in Bifidobacterium adolescentis.
Members of glycoside hydrolase family 1 (GH1) cleave glycosidic linkages with a variety of physiological roles. Here we report a unique GH1 member encoded in the genome of Bifidobacterium adolescentis ATCC 15703. This enzyme, BAD0156, was identified from over 2,000 GH1 sequences accumulated in a database by a genome mining approach based on a motif sequence. A recombinant BAD0156 protein was characterized to confirm that this enzyme alone specifically hydrolyzes p-nitrophenyl-α-L-arabinofuranoside among the 24 p-nitrophenyl-glycosides examined. Among natural glycosides, α-1,5-linked arabino-oligosaccharides served as substrates, but arabinan, debranched arabinan, arabinoxylan, and arabinogalactan did not. A time course analysis of arabino-oligosaccharide hydrolysis indicated that BAD0156 is an exo-acting enzyme. These results suggest that BAD0156 is an α-L-arabinofuranosidase. This is the first report of a GH1 enzyme that acts specifically on arabinosides, providing information on GH1 substrate specificity.
Organization of Advanced Science and Technology, Kobe University.
Hirokazu
H
Suzuki
Ayano
A
Murakami
Ken-ichi
K
Yoshida
D020816:Amino Acid Motifs / Q000235:genetics*; D001644:Bifidobacterium / Q000201:enzymology*; D016680:Genome, Bacterial; D006026:Glycoside Hydrolases / Q000737:chemistry / Q000378:metabolism*; D006027:Glycosides / Q000378:metabolism; D006868:Hydrolysis; D017434:Protein Structure, Tertiary; D013379:Substrate Specificity; D014990:Xylans / Q000378:metabolism
D006027:Glycosides; D014990:Xylans; C085118:arabinoxylan; D006026:Glycoside Hydrolases; C019713:alpha-N-arabinofuranosidase