TY - JOUR
T1 - Enhanced thermostability of mesophilic endoglucanase Z with a high catalytic activity at active temperatures
AU - Kim, Su Jung
AU - Joo, Ji Eun
AU - Jeon, Sang Duck
AU - Hyeon, Jeong Eun
AU - Kim, Seung Wook
AU - Um, Young Soon
AU - Han, Sung Ok
N1 - Funding Information:
We would like to acknowledge financial support from the Industrial Strategic Technology Development Program (10051513) funded by the Ministry of Trade, Industry & Energy (MI, Korea) and the R&D Convergence Program of NST (National Research Council of Science & Technology) of the Republic of Korea/KIST (Korea Institute of Science and Technology) (2E25402).
Publisher Copyright:
© 2016 Elsevier B.V.
PY - 2016/5/1
Y1 - 2016/5/1
N2 - This is the first study for therrmostable mutants of mesophilic endoglucanase EngZ from Clostridium cellulovorans using by site-directed mutagenesis. K94R, S365P and their double mutant K94R/S365P had a wide range of active temperatures (30-60 °C). In addition, the optimal temperature of K94R/S365P was increased by 7.5 °C. K94R/S365P retained 78.3% relative activity at 70 °C, while the wild type retained only 5.8%. Especially, K94R/S365P remained 45.1-fold higher activity than the wild type at 70 °C. In addition, K94R/S365P was 3.1-fold higher activity than the wild type at 42.5 °C, which is the optimal temperature of the wild type. K94R/S365P showed also stimulated in 2.5-fold lower concentration of CaCl2 and delayed aggregation temperature in the presence of CaCl2 compared to the wild type. In pH stability, K94R/S365P was not influenced, but the optimum pH was transferred from pH 7 to pH 6. In long-term hydrolysis, K94R/S365P reduced the newly released reducing sugar yields after 12 h reaction; however, the yields consistently increased until 72 h. Finally, the total reducing sugar of K94R/S365P was 5.0-fold higher than the wild type at 50 °C, pH6. EngZ (K94R/S365P) can support information to develop thermostability of GH9 endoglucanase with a high catalytic efficiency as the potential industrial bioprocess candidate.
AB - This is the first study for therrmostable mutants of mesophilic endoglucanase EngZ from Clostridium cellulovorans using by site-directed mutagenesis. K94R, S365P and their double mutant K94R/S365P had a wide range of active temperatures (30-60 °C). In addition, the optimal temperature of K94R/S365P was increased by 7.5 °C. K94R/S365P retained 78.3% relative activity at 70 °C, while the wild type retained only 5.8%. Especially, K94R/S365P remained 45.1-fold higher activity than the wild type at 70 °C. In addition, K94R/S365P was 3.1-fold higher activity than the wild type at 42.5 °C, which is the optimal temperature of the wild type. K94R/S365P showed also stimulated in 2.5-fold lower concentration of CaCl2 and delayed aggregation temperature in the presence of CaCl2 compared to the wild type. In pH stability, K94R/S365P was not influenced, but the optimum pH was transferred from pH 7 to pH 6. In long-term hydrolysis, K94R/S365P reduced the newly released reducing sugar yields after 12 h reaction; however, the yields consistently increased until 72 h. Finally, the total reducing sugar of K94R/S365P was 5.0-fold higher than the wild type at 50 °C, pH6. EngZ (K94R/S365P) can support information to develop thermostability of GH9 endoglucanase with a high catalytic efficiency as the potential industrial bioprocess candidate.
KW - Cellulolytic efficiency
KW - EngZ
KW - Family 9 endoglucanase
KW - Site-directed mutagenesis
KW - Thermostability
UR - http://www.scopus.com/inward/record.url?scp=84956611496&partnerID=8YFLogxK
U2 - 10.1016/j.ijbiomac.2016.01.068
DO - 10.1016/j.ijbiomac.2016.01.068
M3 - Article
C2 - 26808019
AN - SCOPUS:84956611496
VL - 86
SP - 269
EP - 276
JO - International Journal of Biological Macromolecules
JF - International Journal of Biological Macromolecules
SN - 0141-8130
ER -