Cloning and characterization of a cold-active xylanase enzyme from an environmental DNA library.
There is a great interest in xylanases due to the wide variety of industrial applications for these enzymes. We cloned a xylanase gene (xyn8) from an environmental genomic DNA library. The encoded enzyme was predicted to be 399 amino acids with a molecular weight of 45.9 kD. The enzyme was categorized as a glycosyl hydrolase family 8 member based on sequence analysis of the putative catalytic domain. The purified enzyme was thermolabile, had an activity temperature optimum of 20 degrees C on native xylan substrate, and retained significant activity at lower temperatures. At 4 degrees C, the apparent K (m) was 3.7 mg/ml, and the apparent k (cat) was 123/s.
Lee
Charles C
CC
USDA-ARS-WRRC, 800 Buchanan St., Albany, CA 94710, USA. clee@pw.usda.gov
Kibblewhite-Accinelli
Rena E
RE
Wagschal
Kurt
K
Robertson
George H
GH
Wong
Dominic W S
DW
D000383:Agriculture; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D002140:California; D003001:Cloning, Molecular; D004795:Enzyme Stability; D015723:Gene Library; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D013696:Temperature; D014871:Water Microbiology; D014995:Xylosidases / Q000235:genetics* / Q000302:isolation & purification* / Q000378:metabolism
D001426:Bacterial Proteins; D014995:Xylosidases