COLLABORATIVE RESEARCH: Exploiting microbial hyperthermophilicity to produce an industrial chemical

微生物代谢工程的发展在很大程度上是基于有限数量的重组宿主（例如，大肠杆菌，酿酒酵母），因为对这些微生物的生理学有大量的了解，并且相关的分子遗传工具是可用的。然而，随着代谢工程针对越来越多的创新生物加工目标，迫切需要扩大潜在微生物宿主的范围。因为极端微生物已经被赋予了适应工业过程中恶劣条件的特性，所以为这群微生物开发代谢工程能力是有意义的。这个方向直到最近才被认为是难以置信的，但新开发的分子遗传工具和基因组学研究为极端微生物的代谢工程开辟了前景。因此，这个拟议的项目将证明代谢工程对超嗜热古细菌的功效，炽热焦球菌，在100°C下生长最佳。为了证明这种微生物确实可以进行代谢工程，这项工作将建立在最近在温度依赖性生化处理方面取得的成功的基础上，现在将从纤维素二糖和麦芽糖中生产出一种特殊化学品琥珀酸盐。从最适温度在70°C附近的不太嗜热的生物体中鉴定出的转运蛋白和代谢酶的编码基因将被导入重组卟啉卟啉菌菌株。战略性地利用超嗜热性的基因调控和产物形成的新方法将用于优化70°C附近生物产物形成的产量和效率。提供一个代谢工程的范例，一个超嗜热宿主生产非生理产品，将为热为基础的生物处理机会铺平道路。学生在分子生物化学、功能基因组学和生物分子工程方面的跨学科训练将产生更广泛的影响，以研究极端微生物生物学和生物技术。每年秋季学期将招募两名本科生研究人员，随后在PI的实验室进行夏季研究经验（一名UGA的生物化学家和一名NCSU的化学工程师）。这些学生将在夏季期间在另一个合作实验室度过两周时间，以促进跨学科培训。所有在NCSU和UGA参加这个项目和相关项目的学生将在夏季参加在NSCU和UGA轮流举办的年度“超嗜热菌小组会议”。这将促进跨学科培训和合作，并提供一种交流研究思想和方法的机制。

1264052/1264053 Kelly/AdamsThe development of microbial metabolic engineering has largely been based on a limited number of recombinant hosts (e.g., Escherichia coli, Saccharomyces cerevisiae) because of the substantial knowledge of the physiology of these microorganisms and availabilityof associated molecular genetic tools. However, as metabolic engineering is directed at more and more innovative bioprocessing objectives, there is a pressing need to expand the range of potential microbial hosts. Because extremophiles are already endowed with properties that are amenable to the harsh conditions characteristic of industrial processes, it makes sense to develop metabolic engineering capabilities for this group of microorganisms. This direction would have been implausible until very recently, but newly developed molecular genetic tools and genomics studies have opened up the prospects for metabolic engineering of extremophiles. As such, this proposed project will demonstrate the efficacy of metabolically engineering the hyperthermophilic archaeon, Pyrococcus furiosus, which grows optimally at 100°C. To demonstrate that this microorganism can, indeed, be metabolically engineered, the work will build upon recent success in temperature-dependent biochemical processing and will now produce a specialty chemical, succinate, from cellobiose and maltose. Genes encoding transporters and metabolic enzymes identified from less thermophilic organisms with optimum temperature values near 70°C will be imported into a recombinant P. furiosus strain. Novel approaches for gene regulation and product formation that strategically exploit hyperthermophilicity will be utilized to optimize yields and efficiencies for bioproduct formation near 70°C. Providing a paradigm for metabolically engineering a hyperthermophilic host to produce a non-physiological product will pave the way for thermally-based, bioprocessing opportunities.Broader impacts will result from the interdisciplinary training of students in molecular biochemistry, functional genomics and biomolecular engineering for studying extremophile biology and biotechnology. Two undergraduate researchers will be recruited during each fall semester and be supported subsequently for a summer research experience in the PI's laboratories (one biochemist at UGA and one chemical engineer at NCSU). These students will spend two weeks during the summer at the other collaborating lab to foster interdisciplinary training. All students on this and related projects at NCSU and UGA will participate in an annual extended 'Hyperthermophile Group Meeting' during the summer to be hosted at NSCU and UGA on an alternating basis. This will foster interdisciplinary training and collegiality, as well as provide a mechanism for exchange of research ideas and methodologies.