New alpha-L-arabinofuranosidase produced by Streptomyces lividans: cloning and DNA sequence of the abfB gene and characterization of the enzyme.
A fully secreted alpha-l-arabinofuranosidase was cloned from the homologous expression system of Streptomyces lividans. The gene, located upstream adjacent to the previously described xylanase A gene, was sequenced. It is divergently transcribed from the xlnA gene and the two genes are separated by an intercistronic region of 391nt which contains a palindromic AT-rich sequence. The deduced amino acid sequence of the protein shows that the enzyme contains a distinct catalytic domain which is linked to a specific xylan-binding domain by a linker region. The purified enzyme has a specific arabinofuranose-debranching activity on xylan from Gramineae, acts synergistically with the S. lividans xylanases and binds specifically to xylan. From small arabinoxylo-oligosides, it liberates arabinose and, after prolonged incubation, the purified enzyme exhibits some xylanolytic activity as well.
Vincent
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P
Centre de Recherche en Microbiologie Appliquée, Institut Armand-Frappier, Université du Québec, Ville de Laval, Qué, H7N4Z3, Canada.
Shareck
F
F
Dupont
C
C
Morosoli
R
R
Kluepfel
D
D
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics*; D005798:Genes, Bacterial; D006026:Glycoside Hydrolases / Q000032:analysis / Q000235:genetics* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D017422:Sequence Analysis, DNA; D013302:Streptomyces / Q000235:genetics*
D004269:DNA, Bacterial; D006026:Glycoside Hydrolases; C019713:alpha-N-arabinofuranosidase