Abstract
Abstract Three endoxylanase genes were cloned from the thermophilic
fungus Chaetomium thermophilum CBS 730.95. All genes contained the typical
consensus sequence of family 11 glycoside hydrolases. Genomic copies of Ct
xyn11A, Ct xyn11B, and Ct xyn11C were expressed in the filamentous fungus T.
reesei under the control of the strong T. reesei cel7A (cellobiohydrolase 1,
cbh1) promoter. The molecular masses of the Ct Xyn11A, Ct Xyn11B, and Ct
Xyn11C proteins on sodium dodecyl sulfate polyacrylamide gel electrophoresis
(SDS-PAGE) were 27, 23, and 22 kDa, respectively. Ct Xyn11A was produced
almost as efficiently as the homologous xylanase II from a corresponding
single-copy transformant strain. Ct Xyn11B production level was approximately
half of that of Ct Xyn11A. The amount of Ct Xyn11C was remarkably lower. Ct
Xyn11A had the highest temperature optimum and stability of the recombinant
xylanases and the highest activity at acid-neutral pH (pH 5–7). It was the
most suitable for industrial bleaching of kraft pulp at high temperature.
Original language | English |
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Pages (from-to) | 377 - 386 |
Journal | Applied Microbiology and Biotechnology |
Volume | 76 |
Issue number | 2 |
DOIs | |
Publication status | Published - 2007 |
MoE publication type | A1 Journal article-refereed |
Keywords
- Trichoderma reesei
- xylanases
- Chaetomium thermophilum
- recombinant proteins
- biobleaching
- bleaching
- pulp
- Kraft pulp