- 著者
- Fernanda Miyuki Kashiwagi Yoshihiro Ojima Masahito Taya
- 出版者
- The Society of Chemical Engineers, Japan
- 雑誌
- JOURNAL OF CHEMICAL ENGINEERING OF JAPAN (ISSN:00219592)
- 巻号頁・発行日
- vol.51, no.3, pp.264-268, 2018-03-20 (Released:2018-03-20)
- 参考文献数
- 16
- 被引用文献数
- 2
Cofactor regulation for the production of reduced metabolites, such as ethanol, plays an important role in the metabolic pathways of microorganisms. In this study, the intracellular NADH/NAD+ ratio in the ethanologenic strain Escherichia coli KO11 was increased by the overexpression of formate dehydrogenase from Mycobacterium vaccae. To avoid the generation of pyruvate-derived byproducts, genes coding for the lactate- and acetate-producing pathways were successfully deleted using genome editing based on the CRISPR-Cas9 system. In the culture of the constructed strain, the NADH regeneration system increased the intracellular NADH/NAD+ ratio in the presence of formate, leading to enhanced ethanol production; the amount of ethanol produced was 36% more than that produced by the original KO11 strain in culture for 24 h. A detailed investigation revealed that the transient pyruvate accumulation plays a key role in the enhanced ethanol production using the NADH regeneration system.
- 著者
- HIROYUKI HONDA MASAHITO TAYA TAKESHI KOBAYASHI
- 出版者
- 公益社団法人 化学工学会
- 雑誌
- JOURNAL OF CHEMICAL ENGINEERING OF JAPAN (ISSN:00219592)
- 巻号頁・発行日
- vol.19, no.4, pp.268-273, 1986-08-20 (Released:2006-04-19)
- 参考文献数
- 20
- 被引用文献数
- 21 30
An extractive fermentation for ethanol production was carried out by using immobilized cells of Saccharomyces cerevisiae Kyokai 7 and its lactose-fermentable fusant (strain PN13). Although o-isopropylphenol (OIPP) and o-tert-butylphenol (OTBP) as extractive solvents had relatively large partition coefficients against ethanol (1.4 by weight-based concentration), the solvents were heavily toxic to both yeasts. Some plant oils such as castor oil protected the yeasts from the toxicity of OTBP. Therefore, the ethanol fermentation became feasible even in the presence of OTBP as extractant by using yeast immobilized within alginate gel containing castor oil as protective agent. The ethanol production activity of gel beads containing the oil was not deteriorated through six repeated uses.