Improving thermal stability of xylanase by introducing aromatic residues at the N-terminus.
- Author:
Wenqin BAI
;
Luhong YANG
;
Yanhe MA
- Publication Type:Journal Article
- MeSH:
Endo-1,4-beta Xylanases;
chemistry;
Enzyme Stability;
Hydrogen-Ion Concentration;
Protein Engineering;
Temperature
- From:
Chinese Journal of Biotechnology
2014;30(8):1217-1224
- CountryChina
- Language:Chinese
-
Abstract:
Thermophilic and alkalophilic xylanases have great potential in the pulp bleaching industry. In order to improve the thermal stability of an alkaline family 11 xylanase Xyn11A-LC, aromatic residues were introduced into the N-terminus of the enzyme by rational design. The mutant increased the optimum temperature by 5 degrees C. The wild type had a half-time of 22 min at 65 degrees C and pH 8.0 (Tris-HCl buffer). Under the same condition, the mutant had the half-time of 106 min. CD spectroscopy revealed that the melting temperature (T(m)) values of the wild type and mutant were 55.3 degrees C and 67.9 degrees C, respectively. These results showed that the introduction of aromatic residues could enhance the thermal stability of Xyn11A-LC.