Effects of Linker on the Thermal Adaptability of β-Xylosidase HJ14GH43
CSTR:
Author:
Affiliation:

(1.College of Life Science, Yunnan Normal University, Kunming 650500;2.Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming 650500;3.Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment, Kunming 650500;4.Key Laboratory of Yunnan Provincial Education Department for Plateau Characteristic Food Enzymes,Yunnan Normal University, Kunming 650500)

Clc Number:

Fund Project:

  • Article
  • |
  • Figures
  • |
  • Metrics
  • |
  • Reference
  • |
  • Related
  • |
  • Cited by
  • |
  • Materials
  • |
  • Comments
    Abstract:

    In this study, the mutant MutLK10 was constructed by replacing the linker of β-xylosidase HJ14GH43 in order to reveal the mechanism of the linker on thermal adaptability of the β-xylosidase. MutLK10 was successfully expressed by Escherichia coli BL21 (DE3). Then, the enzymatic characteristics and 3D structure of MutLK10 were analyzed. The results showed that the optimum temperature of mutant MutLK10 was 20 ℃, which was 5 ℃ lower than that of the wild-type enzyme HJ14GH43. MutLK10 retained approximately 28% and 69% relative activities after being incubated at 20 ℃ and 10 ℃ for 60 min, respectively. Whereas HJ14GH43 retained approximately 70% and 88% relative activities after incubation at 20 ℃ and 10 ℃ for 60 min, respectively. Thus, MutLK10 had lower optimum temperature and worse thermalstability than HJ14GH43. The linkers of HJ14GH43 and MutLK10 were constructed as coil regions on the surfaces of proteins. Structural analysis showed that the negative potentials of the coil regions increased after the mutation, which led to the increase of hydrophilicity. It indicates that increasing the proportion of acidic amino acids in the linker can help the β-xylosidase compete for hydration by increasing the surface negative electrostatic potentials, that may result in the increase of the interactions between the enzyme and solvents and finally enables the enzyme to adapt to low-temperature environments. This study provides a reference for thermal adaptability modification of β-xylosidases and other industrial enzymes.

    Reference
    Related
    Cited by
Get Citation
Share
Article Metrics
  • Abstract:
  • PDF:
  • HTML:
  • Cited by:
History
  • Received:June 29,2022
  • Revised:
  • Adopted:
  • Online: August 17,2023
  • Published:
Article QR Code
Copyright :Journal of Chinese Institute of Food Science and Technology     京ICP备09084417号-4
Address :9/F, No. 8 North 3rd Street, Fucheng Road, Haidian District, Beijing, China      Postal code :100048
Telephone :010-65223596 65265376      E-mail :chinaspxb@vip.163.com
Supported by : Beijing E-Tiller Technology Development Co., Ltd.