Cloning and heterologous expression of a glucodextranase gene from Arthrobacter globiformis I42, and experimental evidence for the catalytic diad of the recombinant enzyme.
The gene encoding a glucodextranase from Arthrobacter globiformis I42 was cloned and, subsequently, heterologously expressed in Escherichia coli. This glucodextranase gene consists of 1048 amino acid residues with a calculated molecular mass of 109,135 Da. The roles of two residues at the active site of A. globiformis I42 glucodextranase were examined by site-directed mutagenesis. Glutamic acid residues 458 and 656, which are part of the apparent catalytic residues, were found to be essential for hydrolase activity.
Morimoto
Naoki
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Department of Applied Bioscience, Graduate School of Agriculture, Hokkaido University, Kita-9, Nishi-9, Sapporo 060-8589, Japan.
Yasukawa
Yoshitaka
Y
Watanabe
Kenji
K
Unno
Takehiro
T
Ito
Hiroyuki
H
Matsui
Hirokazu
H