|
Poster Presentation 2-17
Effects of Xylose Reductase Gene activity on Xylitol Production in Recombinant Saccharomyces cerevisiae
Yun-Seung Chung, Young-Sok Jeun1, Dea-Hee Lee1, Myoung-Dong Kim, Yeon-Woo Ryu2, Jung-Kul Lee3, Ji-Hyun Kim4, and Jin-Ho Seo
Department of Food Science and Technology and Research Center for New Bio-Materials in Agriculture, Seoul National University, Suwon 441-744, Korea
1School of Agricultural Biotechnology, Seoul National University, Suwon 441-744, Korea 2Department of Molecular Science and Technology, Ajou University, Suwon 442-749, Korea 3Bolak Company Limited, Kyonggi-Do, 307-1, Korea 4Ministry of Commerce, Industry and Energy, Kwacheon 427-010, Korea
Telephone: (82) 31-290-2583; Fax: (82) 31-293-4789; E-mail: jhseo94@snu.ac.kr
Effects of the expression mode of the xylose reductase gene (XYL1) on xylitol production in recombinant Saccharomyces cerevisiae strains were investigated in batch and fed-batch cultures. The gene coding for xylose reductase (XR) was introduced into S. cerevisiae in two different ways: by using a d-integration vector for chromosome-integration and a YRp-based episomal plasmid vector. The two expression systems showed the different pattern of xylitol production in a glucose-limited fed-batch culture as opposed to the similar profile in a batch culture. The recombinant S. cerevisiae strain harboring the XR gene in the chromosome yielded a 1.70-fold enhancement in xylitol productivity in the fed-batch culture compared with the YRp-based xylose reductase expression strain. Such an improvement for the integrated recombinant strain was supported by the fact that the mitotic stability of the XR gene along with its high expression level worked in a cooperative manner.
Keywords: Xylitol, xylose reductase, δ-integration, mitotic stability
|