TY - JOUR
T1 - Molecular cloning and expression of fungal cellobiose transporters and β-glucosidases conferring efficient cellobiose fermentation in Saccharomyces cerevisiae
AU - Bae, Yi Hyun
AU - Kang, Kyeong Hyeon
AU - Jin, Yong Su
AU - Seo, Jin Ho
N1 - Funding Information:
This research was supported by Advanced Biomass R&D Center (ABC) ( 2011-0031359 ) and the Korea Research Council of Fundamental Science & Technology (KRCF) Grant, Korea. Yong-Su Jin is affiliated with the Energy Biosciences Institute.
PY - 2014/1/10
Y1 - 2014/1/10
N2 - Cellobiose was once regarded as a byproduct that should be removed from biomass hydrolysates because of its inhibitory activity to cellulases. It was revealed, however, that cellobiose could serve as a co-substrate for xylose fermentation by engineered Saccharomyces cerevisiae. Despite its advantages, to date, little is known about cellodextrin transporters that endow S. cerevisiae with cellobiose transporting ability. In this study, engineered S. cerevisiae strains capable of fermenting cellobiose were constructed by expressing various fungal cellobiose transporters and intracellular β-glucosidases. Among them, the strain expressing a putative sugar transporter from Penicillium chrysogenum (Pc_ST) and β-glucosidase from Thielavia terrestris (Tt_BG) showed an improved cellobiose fermentation performance compared to the strain expressing a cellodextrin transporter from Neurospora crassa (Nc_CDT-1) and β-glucosidase from N. crassa (Nc_GH1-1). Cellobiose fermentation by S. cerevisiae Pc_ST/Tt_BG under microaerobic conditions resulted in 14.5 ± 0.5. g/L of final ethanol concentration with a yield of 0.37 ± 0.01. g ethanol/g cellobiose, which are 22% and 26% higher than the corresponding values of S. cerevisiae Nc_CDT-1/Nc_GH1-1. These results suggest that the yield and rate of cellobiose fermentation can be improved by adopting optimal pairs of cellobiose transporters and β-glucosidase.
AB - Cellobiose was once regarded as a byproduct that should be removed from biomass hydrolysates because of its inhibitory activity to cellulases. It was revealed, however, that cellobiose could serve as a co-substrate for xylose fermentation by engineered Saccharomyces cerevisiae. Despite its advantages, to date, little is known about cellodextrin transporters that endow S. cerevisiae with cellobiose transporting ability. In this study, engineered S. cerevisiae strains capable of fermenting cellobiose were constructed by expressing various fungal cellobiose transporters and intracellular β-glucosidases. Among them, the strain expressing a putative sugar transporter from Penicillium chrysogenum (Pc_ST) and β-glucosidase from Thielavia terrestris (Tt_BG) showed an improved cellobiose fermentation performance compared to the strain expressing a cellodextrin transporter from Neurospora crassa (Nc_CDT-1) and β-glucosidase from N. crassa (Nc_GH1-1). Cellobiose fermentation by S. cerevisiae Pc_ST/Tt_BG under microaerobic conditions resulted in 14.5 ± 0.5. g/L of final ethanol concentration with a yield of 0.37 ± 0.01. g ethanol/g cellobiose, which are 22% and 26% higher than the corresponding values of S. cerevisiae Nc_CDT-1/Nc_GH1-1. These results suggest that the yield and rate of cellobiose fermentation can be improved by adopting optimal pairs of cellobiose transporters and β-glucosidase.
KW - β-glucosidase
KW - Cellobiose fermentation
KW - Cellodextrin transporter
KW - Ethanol
KW - Saccharomyces cerevisiae
UR - http://www.scopus.com/inward/record.url?scp=84888769998&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84888769998&partnerID=8YFLogxK
U2 - 10.1016/j.jbiotec.2013.10.030
DO - 10.1016/j.jbiotec.2013.10.030
M3 - Article
C2 - 24184384
AN - SCOPUS:84888769998
SN - 0168-1656
VL - 169
SP - 34
EP - 41
JO - Journal of Biotechnology
JF - Journal of Biotechnology
IS - 1
ER -