Enhancing stability of Trichoderma reesei xylanase (XYN II) by site-directed mutagenesis / 生物工程学报
Chinese Journal of Biotechnology
; (12): 623-629, 2010.
Article
in Zh
| WPRIM
| ID: wpr-292228
Responsible library:
WPRO
ABSTRACT
We engineered a disulphide bridge between two adjacent double-layered beta-sheet at the N-terminal region of Trichoderma reesei endo-1,4-beta-xylanase II(XYN II) by site-directed mutagenesis. The native xylanase XYN-OU and the mutated xylanase XYN-HA12 (T2C, T28C and S156F) were separately expressed in Pichia pastoris. Both xylanases were purified and characterized. The optimum temperature of XYN-HA12 was increased from 50 degrees C to 60 degrees C, relative to XYN-OU. At 70 degrees C, the halftime of inactivation for XYN-OU and XYN-HA12 were 1 min and 14 min, respectively. The optimum pH of XYN-HA12 was 5.0, similar to XYN-OU. However, XYN-HA12 could retain over 50% activity from pH 3.0 to 10.0 at 50 degrees C for 30 min. As for XYN-OU, it could retain over 50% activity from the pH value 4.0 to 9.0 at 50 degrees C in 30 min. The result of the mutated xylanase indicated that constructed disulphide bridge could improve its thermostability at relatively higher temperature.
Full text:
1
Index:
WPRIM
Main subject:
Pichia
/
Trichoderma
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Enzyme Stability
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Recombinant Proteins
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Protein Engineering
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Chemistry
/
Mutagenesis, Site-Directed
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Amino Acid Substitution
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Endo-1,4-beta Xylanases
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Disulfides
Language:
Zh
Journal:
Chinese Journal of Biotechnology
Year:
2010
Type:
Article