抄録
Alkaliphilic microbes were screened for
chitin-degrading activity. An alkaline-active chitinolyticenzyme producer was isolated from soil and identified as
Nocardiopsis sp. strain F96. A chitinase gene was cloned
from strain F96 using GH family 18 Streptomyces
lividans chiA as a probe. The cloned chitinase gene,
chiF1, contained an open reading frame of 1,011
nucleotides encoding 337 amino acids of precursor
enzyme. Deduced amino acid sequence of ChiF1,
encoded by chiF1, had similarity with catalytic domains
of GH18 chitinases, that contained the highly conserved
DXDXE motif. For expression of chiF1 in Escherichia
coli, the expression vector pETchiF1 was constructed.
Chitinase activity was mainly observed in the
extracellular fraction of E. coli harboring pETchiF1.
Optimum pH and temperature for activity of recombinant
ChiF1 were pH 7.5 and 60°C, respectively.
