|
KMID : 0545120040140010171
|
|
Journal of Microbiology and Biotechnology
2004 Volume.14 No. 1 p.171 ~ p.177
|
|
|
Xylan Hydrolysis by Treatment with Endoxylanase and β-Xylosidase Expressed in Yeast
|
|
HEO, SUN-YEON
KIM, JOONG-KYUN/KIM, YOUNG-MAN/KIM, SOO-WAN
|
|
|
Abstract
|
|
|
|
The endoxylanase (642 bp; 2 13 amino acids) and P-xylosidase (1,602 bp; 533 amino acids) genes from Bacillus sp. were amplified by PCR and separately inserted into the downstream of the yeast ADHl promoters, resulting in the pAEDX-1 (7.63 kb) and pAEX (8.47 kb) plasmids, respectively. When the yeast transformants, S. cerevisiae SEY2102 harboring pAEDX-1 or pAEX, were grown on YPD medium, the total activities of the enzymes were approximately 9.8 unit/ml for endoxylanase and 2.9 unit/ml for P-xylosidase. When the three kinds of xylan from oat spelts, birch wood, and corncob were hydrolyzed by treating with recombinant endoxylanase and P-xylosidase, it was found that xylose, xylobiose, and xylotriose were produced. To efficiently hydrolyze xylan, various reaction conditions such as amount of enzymes, substrate type, substrate concentration, temperature, and reaction time were examined. The optimized conditions for the hydrolysis of xylan were as follows: amount of endoxylanase, 10 units; amount of β-xylosidase, 10 units; temperature, 50℃; substrate type, oat spelts xylan; substrate concentration, 6%; reaction time, 1 h. Under the optimal condition, xylose was mainly produced from oat spelts xylan by cooperative action of endoxylanase and β-xylosidase.
|
|
|
KEYWORD
|
|
|
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
  
|
|