Genome-wide analysis of mRNA transcripts in Pichia stipits reveals new targets for metabolic engineering of xylose fermentation in Saccharomyces cerevisiae
P. stipitis, the best known xylose fermenting yeast, has been served as a gene source for metabolic engineering of xylose fermentation in S. cerevisiae. Specifically, three genes (XYL1, XYL2, and XYL3) coding for the xylose metabolic pathway enzymes (xylose reductase, xylitol dehydrogenase, and xyluokinase) have been introduced into S. cerevisiae. The resulting recombinant S. cerevisiae strains were able to assimilate xylose as a carbon source, but did not produce ethanol with high yields. Accumulated results from prior studies suggested that simultaneous perturbation of multiple genes might be required to facilitate high yield xylose fermentation in S. cerevisiae. In order to identify such a set of gene targets enhancing xylose fermentation, we investigated the levels of mRNA transcripts of P. stipitis grown under four different conditions through EST analysis. We discovered two notable features in the gene expression profiles. First, transcripts of glucose-6-phsphate dehydrogenase (GND1), transketolase (TKT1), and transaldolase (TAL1), involved in the pentose phosphate pathway, are strongly induced on xylose. Second, the expression of a NAD-specific glutamate dehydrogenase (GDH2) is elevated on xylose under oxygen limited conditions. These results suggest that higher capacity of the pentose pathway and a cofactor regeneration system are necessary for efficient maintenance of xylose metabolism.
저자
Yong-Su Jin [ Department of Food Science and Biotechnology, Sungkyunkwan University ]
Thomas Jeffries [ Department of Bacteriology, University of Wisconsin-Madison ]
한국생물공학회 [The Korean Society for Biotechnology and Bioengineering]
설립연도
1984
분야
공학>생물공학
소개
이 법인은 생물 공학의 발전과 보급에 이바지하고, 회원 상호 간의 연구 협력과 친목을 도모함을 목적으로 한다
1. 생물공학 분야의 발전을 위한 연구 협력
2. 생물공학의 실용화를 촉진시키기 위한 산학 협동
3. 학술연구 발표회, 강연회, 연수회 등 학술활동의 개최
4. 국,영문 학술지,소식지,학술회의 Proceedings 및 학술도서의 발간
5. 생물공학 발전을 위한 정책 건의
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