1. Biosci Biotechnol Biochem. 2002 Feb;66(2):434-8.

Cloning and expression of an alpha-L-arabinofuranosidase gene (stxIV) from
Streptomyces thermoviolaceus OPC-520, and characterization of the enzyme.

Tsujibo H, Takada C, Wakamatsu Y, Kosaka M, Tsuji A, Miyamoto K, Inamori Y.

Osaka University of Pharmaceutical Sciences, Takatsuki, Japan.
tsujibo@gly.oups.ac.jp

The gene encoding alpha-L-arabinofuranosidase (STX-IV), located upstream of the
previously reported stxI gene, was cloned and sequenced. The gene is divergently 
transcribed from the stxI gene, and the two genes are separated by 661
nucleotides. The stxIV gene consists of a 1,092-bp open reading frame encoding
363 amino acids. The deduced amino acid sequence of the gene showed that STX-IV
was an enzyme consisting of only a catalytic domain, and that the enzyme had
significant similarity with alpha-L-arabinofuranosidases belonging to family 62
of glycosyl hydrolases. The stxIV gene was expressed in Escherichia coli, and the
recombinant protein was purified to homogeneity. Arabinoxylan and oat spelt xylan
were good substrates for STX-IV, however, the enzyme showed a low activity with
p-nitrophenyl alpha-L-arabinofuranoside. The optimum pH and temperature were 5.0 
and 60 degrees C, respectively.

PMID: 11999423 [PubMed - indexed for MEDLINE]