Microbial Physiology of Alcohol and Hydrogen Production at High Temperatures

*我的研究计划专注于通过研究在高温下从大量可获得的非食品生物质中高效生产酒精和氢气的机制来开发可再生能源。这是通过表征和修改代谢途径中涉及的新的酶和电子转移活动，以及分离能够产生更多酒精或氢气的新的超嗜热菌(在高温下茁壮成长的微生物)来实现的。并不是所有参与酒精产生代谢途径的关键酶都是已知的，也不是电子转移酶在提高高温下酒精和氢气生产效率方面的调节作用。这种认识的缺乏阻碍了更有效的生物转化系统的发展。我的研究目标是：1)研究生长在90℃及以上的产醇和产氢高温微生物的生理和应用；2)研究它们的新型耐热酶，如酒精脱氢酶、产醛酶、电子转移酶和氢酶，并阐明它们的代谢功能和在生物催化和生产酒精和氢气作为生物燃料方面的潜在应用。这将包括鉴定新的分离株，确定所研究的每种酶的生物物理和生化性质，研究它们在代谢途径中的催化作用，以及探索蛋白质热稳定性的机制。生物技术的潜在应用包括绿色化学和大量可获得的非食用木质纤维废物的更强劲的生物转化。将使用高温古生菌(Hyperthermus buylicus，Tmax=112 C，产生丁醇)和细菌(Thermotoga maritima，Tmax=90 C，产生乙醇和H2)来研究与酒精和H2代谢相关的机制。将利用生化和分子技术研究酶的表达和调控，并对关键酶进行纯化和表征。将相应地进行基因克隆和诱变。在发现的新分离株中，将有一到两个进行研究。这项工作的成功完成在加拿大将是独一无二的。它将提供对高温酒精和氢气代谢和蛋白质热稳定性的进一步洞察，并阐明高温下酒精和氢气产生的代谢途径的调节。研究结果可应用于建设更高效的绿色能源生产系统(如乙醇、丁醇、氢气)，并将有助于应对气候变化和因消耗有限的化石燃料而导致的环境恶化的负面影响。HQP将获得进行微生物学、分子生物学和生化研究的技能和经验，为他们在学术界以及食品、生物技术和制药行业的职位做好准备。

***My research program focuses on developing renewable energy sources by studying the mechanisms of highly efficient alcohol and H2 production from largely available non-food biomass at high temperatures. This is achieved by characterizing and modifying novel enzymes and electron transfer activities involved in the metabolic pathways and isolating new hyperthermophiles (microbes that thrive at high temperatures) capable of producing greater amounts of alcohols or H2. Not all key enzymes involved in the metabolic pathways of alcohol production are known, nor are the regulatory roles of electron transfer enzymes in enhancing the efficiency of alcohol and H2 production at high temperatures. This lack of understanding hinders the development of more efficient bioconversion systems. My research objectives are to 1) investigate the physiology and applications of alcohol- and H2-producing hyperthermophilic microorganisms growing at 90 C and above, and 2) characterize their novel thermostable enzymes, such as alcohol dehydrogenases, aldehyde-producing enzymes, electron transfer enzymes, and hydrogenases, and elucidate their metabolic functions and potential applications in bio-catalysis and the production of alcohols and H2 as biofuels. This will include characterizing new isolates, determining the biophysical and biochemical properties of each enzyme studied, investigating their catalytic roles in metabolic pathways, and exploring mechanisms of protein thermostability. Potential applications in biotechnology include green chemistry and more robust bioconversion of largely available non-food lignocellulosic waste materials. The mechanisms related to alcohol and H2 metabolism will be investigated using both hyperthermophilic archaea (Hyperthermus butylicus, Tmax=112 C, a butanol producer) and bacteria (Thermotoga maritima, Tmax=90 C, an ethanol and H2 producer). The expression and regulation of enzymes will be studied using biochemical and molecular techniques, with key enzymes purified and characterized. Gene cloning and mutagenesis will be carried out accordingly. Of the new isolates found, one or two will be studied. Successful completion of this work will be unique in Canada. It will provide further insights into hyperthermophilic alcohol and H2 metabolism and protein thermostability, and elucidate the regulation of metabolic pathways for the production of alcohols and H2 at high temperatures. The results can be applied to the construction of more efficient systems for green energy production (e.g., ethanol, butanol, H2) and will serve to combat the negative impacts of climate change and environmental deterioration caused by consuming finite fossil fuels. HQP will gain skills and experience conducting microbiological, molecular biological and biochemical research, preparing them for positions in academia and the food, biotechnological, and pharmaceutical industries.