Project/Area Number |
04453125
|
Research Category |
Grant-in-Aid for General Scientific Research (B)
|
Allocation Type | Single-year Grants |
Research Field |
発酵工学
|
Research Institution | Nagoya University |
Principal Investigator |
KOBAYASHI Takeshi Dept.of Biotechnology, Nagoya University, Professor, 工学部, 教授 (10043324)
|
Co-Investigator(Kenkyū-buntansha) |
HONDA Hiroyuki Dept.of Biotechnology, Nagoya University, Associate Professor, 工学部, 助教授 (70209328)
朴 龍洙 名古屋大学, 工学部, 助手 (90238246)
|
Project Period (FY) |
1992 – 1993
|
Project Status |
Completed (Fiscal Year 1993)
|
Budget Amount *help |
¥6,300,000 (Direct Cost: ¥6,300,000)
Fiscal Year 1993: ¥2,800,000 (Direct Cost: ¥2,800,000)
Fiscal Year 1992: ¥3,500,000 (Direct Cost: ¥3,500,000)
|
Keywords | Fermentation / Yeast / Online measurement system / High cell density culture / Recombinant cell / Growth-inhibitive metabolite / Fuzzy control / Bacillus sps. |
Research Abstract |
1. High cell density fermentation of recombinant Bacillus sps. is difficult because they produce growth-inhibitive metabolites under enough nutrient condition. The growth-inhibitive metabolites contain organic acids such as acetic acid, lactic acid and so on. Due to reduction of the organic acid production using an online control system, and effective fermentation of high cell density fermentation and high expression of gene products were realized. 2. We researched most effective host-promoter system for gene product. S.cerevisiae20B-12 and S.cerevisiaeYNN27 were used for host strains ans PGK, SUC2 nd GAL7 promoters were used. From the results of comparison between these recombinant cells, S.cerevisiae20B-12/PGK system was the best in growth rate and yeild of product. 3. In the case of heterologous protein production using recombinant yeasts, glucose concentrarion and ethanol concentration of medium are important factors of these effective produciton. In this study, we researched an effect of ethanol concentration. The heterologous protein production was inhibited by ethanol higher than 5 g/l. It was clear that a maintenance of low ethanol concentration was effective for fermentation process. 4. Online control system was developed for regulating both glucose and ethanol concentration. Cell, dissolved oxygen, glucose and ethanol concentrations were used for operating variables and a fuzzy rule of these variables was used for control of the fermentation system. The production of the gene product in this fuzzy control system was twice as much compared with a conventional fermentation.
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