Cloning of Bacillus licheniformis xylanase gene and characterization of recombinant enzyme.
Hemicellulose is a major component of lignocellulose biomass. Complete degradation of this substrate requires several different enzymatic activities, including xylanase. We isolated a strain of Bacillus licheniformis from a hot springs environment that exhibited xylanase activity. A gene encoding a 23-kDa xylanase enzyme, Xyn11, was cloned, and the recombinant protein was expressed in an Escherichia coli host and biochemically characterized. The optimum activity of the enzyme was at pH 5-7 and 40-50 degrees C. The enzyme was stable at temperatures up to 50 degrees C. Against birchwood xylan, the enzyme had an apparent K(m) of 6.7 mg/mL and V(max) of 379 micromol/min/mg.
Lee
Charles C
CC
USDA-ARS-WRRC, 800 Buchanan St., Albany, CA 94710, USA. Charles.C.Lee@ars.usda.gov
Kibblewhite-Accinelli
Rena E
RE
Smith
Michael R
MR
Wagschal
Kurt
K
Orts
William J
WJ
Wong
Dominic W S
DW
D000595:Amino Acid Sequence; D001407:Bacillus / Q000201:enzymology* / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D003001:Cloning, Molecular; D043364:Endo-1,4-beta Xylanases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D004795:Enzyme Stability; D004926:Escherichia coli / Q000235:genetics; D045482:Hot Springs / Q000382:microbiology; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D013696:Temperature
D001426:Bacterial Proteins; D011994:Recombinant Proteins; D043364:Endo-1,4-beta Xylanases