Engineered Biofilm Catalysts

从历史上看，生物膜主要被认为是有问题的;与感染、龋齿、海洋和反应器结垢以及传热减少相关。在它们的自然环境中，单个的细胞倾向于在表面和界面处聚集在一起。在这些集群中，它们通过分泌胞外聚合物（EPS）保护和粘附多糖基质来保护自己免受环境和化学应激。这种EPS为生物膜提供了一定程度的保护，以防止个别细胞无法耐受的极端pH值、温度或有机溶剂的引入。在当前全球气候下，寻找越来越多的绿色方法来合成精细化学品和药物，人们对利用生物转化越来越感兴趣：利用细胞生产有用的产品。虽然这种策略能够产生对映体纯的化合物，减少合成路线中的步骤，并可能消除对环境有害的催化剂、溶剂和试剂，但由于单个细胞通常不能耐受所需的极端条件，因此它们的使用是有问题的。在这项研究中，我们利用生物膜生产高活性的工程生物膜催化剂（EBC）。这是一个新的领域，因为生物转化中生物膜的使用主要局限于废水处理和生物修复，通常由混合的微生物群落称为财团。使用生物膜合成化合物的报道很少，工业上以这种方式产生的化合物的列表比简单的化合物例如乙酸、乙醇、丁醇、2，3-丁二醇、乳酸、富马酸和琥珀酸更广泛。这个跨学科的提案提出了一种新的方法，用于开发和利用工程生物膜催化剂（EBC），用于与精细化工和制药工业相关的生物转化。最近，我们已经证明了工程生物膜催化剂（EBC）的产生和利用。固定化的EBC不仅表现出前所未有的稳定性，而且被证明是比游离细胞更好的催化剂。由于EBC是人工生成的，因此有相当大的范围来设计其微观结构。我们建议探索EBC催化的一般应用，以及研究微观结构和基因表达与催化活性的关系。我们将采用EBC使用流动化学生成一个原型EBC反应器的生物转化作为未来的工业开发的典范。

Historically, biofilms are predominantly perceived as problematic; associated with infections, dental caries, marine and reactor fouling and reduction in heat transfer. In their natural environment individual planktonic cells have the tendency to cluster together at surfaces and interfaces. Within these clusters they protect themselves from environmental and chemical stress by secreting extracellular polymeric substances (EPS) a protective and adhesive polysaccharide matrix. This EPS gives the biofilm a degree of protection against extremes of pH, temperature or the introduction of organic solvents which cannot be tolerated by individual cells. In the current global climate of searching for increasingly green approaches to the synthesis of fine chemicals and pharmaceuticals there is a growing interest in employing biotransformations: using cells to produce useful products. Although such a strategy enables the generation of enantiomerically pure compounds, the reduction of steps in a synthetic route and the possibility of eliminating environmentally detrimental catalysts, solvents and reagents, their use is problematic due to the fact that individual cells cannot in general tolerate the extreme conditions required. In this research we exploit biofilms to produce highly active Engineered Biofilm Catalysts (EBC). This is a new area as the use of biofilms in biotransformations has been largely confined to wastewater treatment and bioremediation generally by mixed microbial communities referred to as consortia. Reports of the use of biofilms for synthesis of compounds are few and far between, industrially the list of compounds generated in such a manner is little more extensive than simple compounds such as acetic acid, ethanol, butanol, 2,3-butanediol, lactic acid, fumaric acid, and succinic acid. This interdisciplinary proposal presents a novel methodology for the development and exploitation of engineered biofilm catalysts (EBC) for biotransformations relevant to the fine chemicals and pharmaceutical industries. Recently we have demonstrated the generation and utilisation of an Engineered Biofilm Catalyst (EBC). The immobilised EBC not only demonstrated unprecedented stability but proved to be a strikingly better catalyst than the free cells. As the EBC is artificially generated there is considerable scope to engineer its microstructure. We propose to explore the general application of EBC to catalysis as well as to investigate how microstructure and gene expression relate to catalytic activity. We will employ EBC using flow chemistry to generate a prototype EBC reactor for biotransformations as an exemplar for future industrial exploitation.