Microbial Process Improvement Through Energy Stress

通过能量压力改进微生物过程

• 批准号: 8820141
• 负责人: Lenore Clesceri
• 金额: $ 4.91万
• 依托单位: Rensselaer Polytechnic Institute
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-03-01 至 1990-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8820141&HistoricalAwards=false
• 关键词: Microbial; Process; Improvement; Through; Energy

Energy stress has a profound effect on yeast metabolism and can promote aerobic formation of ethanol with high specific productivity. Oxidoreductive metabolism induced by elevated concentrations of glucose cuts in sooner when the cells are further stressed by depressed levels of potassium ion. Although this opens new approaches for ethanol with aerobic instead of anaerobic conditions, progress is slowed by inhibition as ethanol accumulates. It cannot yet be demonstrated that both high ethanol productivity and high concentration can be achieved. This research uses auxostat mode of continuous culture with self-adjustment by the organisms of their feed rate. State-of-the-art computer control stabilizes the cultures. This work includes, 1. testing of various strains of yeast; 2. investigate effects of energy stress on Zymomonas, a bacterium used commercially to produce ethanol; and 3. operate with flocculating yeast to establish high reactor cell densities. Ethanol produced by microorganisms already competes with ethanol made from petroleum and promises to assume an expanding role in automotive fuels. Greater productivity and a rugged aerobic process would lower costs. Preliminary work demonstrates outstanding productivity per cell but cannot maintain it as ethanol accumulates to inhibit the process. This is an important, real effect, and the challenge is to extend it to commercially relevant ranges of ethanol concentration. This research tests other yeasts and a bacterium, Zymomonas, to exploit new insights into a region of physiology that has had little attention. The novel computerized continuous culture apparatus feeds the cells at a rate determined by their own metabolism. This is unique in displaying growth rate responses to changes in conditions and leads to efficient screening of key experimental factors.

能量压力对酵母代谢有深远的影响， 促进具有高比生产率的乙醇的需氧形成。 氧化还原代谢诱导的高浓度的 当细胞进一步受到压力时， 降低钾离子水平。 尽管这开辟了新的途径 对于乙醇与有氧而不是厌氧条件，进展是 随着乙醇的积累而被抑制。 还不能 证明了高乙醇生产率和高 可以实现集中。 本研究采用恒压模式， 通过其饲料的生物体进行自我调节的连续培养 率 最先进的电脑控制稳定了培养物。 这项工作包括，1。测试各种酵母菌株; 2. 研究能量胁迫对发酵单胞菌（Zymomonas）影响， 商业上生产乙醇;和3.操作时， 酵母以建立高的反应器细胞密度。 由微生物生产的乙醇已经在与 并承诺在汽车行业发挥越来越大的作用 燃料. 更高的生产力和坚固的有氧过程将降低 成本 初步工作显示出出色的生产力， 细胞，但不能维持它作为乙醇积累，以抑制 过程 这是一个重要的、真实的影响，挑战在于 将其扩展到 商业上相关的乙醇浓度范围。 这 研究测试了其他酵母和细菌，发酵单胞菌， 探索生理学领域的新见解， 很少注意。 新型计算机化连续培养 装置以由细胞自身决定的速率给细胞供料， 新陈代谢. 这在显示增长率响应方面是独一无二的 条件的变化，并导致关键的有效筛选 实验因素