ERA-IB 5: Biological conversion of CO2 to the platform chemical 3-hydroxypropanoic acid

目前的能源和化学需求是通过开采和加工化石燃料来满足的，这种资源是有限的，它们的使用会造成环境污染和温室气体(GHG)排放。因此，人类面临的挑战是为化学和能源生产确定新的、可持续的和更清洁的工艺。生物途径是一个有希望的选择，但迄今为止的战略依赖于使用微生物通过发酵将植物(如甘蔗或玉米)中容易获得的碳水化合物(糖和淀粉)转化为化学品和燃料。这导致了人们对使用这些碳水化合物作为食物的竞争的担忧，并重新将重点放在非食物的植物细胞壁材料(木质纤维素)上。然而，木质纤维素极难被分解成发酵所需的糖。事实证明，以经济高效的方式克服这种顽固不化是非常具有挑战性的。然而，有一个令人兴奋的低成本替代方案，那就是通过利用某些细菌‘吃掉’单一碳温室气体(如二氧化碳)的能力来直接捕获碳。气体被注入发酵容器的液体介质中，在那里被细菌消耗并转化为我们需要的化学物质。幸运的是，这种气体是一种丰富的资源，可能来自非食品来源，如工业废气以及非食品生物质和家庭/农业废物气化(加热)产生的“合成气”。在这个项目中，我们将利用这一技术来制备平台化学品羟丙酸。它有多种用途，包括制造塑料、涂料、粘合剂、地板抛光剂和油漆。通过使用非食物废气作为原料，避免了与食物和土地资源的竞争，同时通过减少温室气体排放为环境和社会提供了好处。

Current energy and chemical needs are met by the extraction and processing of the fossil fuels.Such resources are finite and their use causes environmental pollution and greenhouse gas (GHG) emissions. The challenge facing humankind is, therefore, to identify new, sustainable and cleaner processes for chemical and energy generation. Biological routes represent a promising option, but strategies to date rely on the use of microbes to convert through fermentation the easily accessible carbohydrates (sugar and starch) of plants (such as sugar cane or corn) into chemicals and fuels. This has led to concerns over competition with the use of these carbohydrates as food, and a re-focussing of efforts on non-food, plant cell wall material (lignocellulose). However, lignocellulose is extremely resistant to being broken down into the sugar needed for fermentation. Overcoming this recalcitrance in a cost effective manner is proving extremely challenging.There is, however, an exciting low-cost alternative, and that is to directly capture carbon, by harnessing the ability of certain bacteria to 'eat' single carbon GHG gases such as CO2. The gas is injected into the liquid medium of fermentation vessels where it is consumed by the bacteria and converted into the chemicals we need. Fortunately, such gases are an abundant resource, and may be derived from non-food sources such as waste gases from industry as well as 'synthesis gas' produced from the gasification (heating) of non-food biomass and domestic/ agricultural wastes. In this project, we will use this technology to make the platform chemical hydroxypropanoic acid. It has a multitude of uses, including the manufacture of plastics, coatings, adhesives, floor polishes and paints. By using non-food, waste gas as a feedstock, competition with food and land resources is avoided while at the same time providing benefits to the environment and society through a reduction in GHG emissions.