Exploiting membrane enzymes in biotechnology: Bioelectrocatalysis and fuel cells

越来越明显的是，为了应对全球变暖和减少我们对化石燃料的依赖，需要采取各种方法，需要将新技术结合起来。许多形式的可再生能源，如太阳能电池和风车，提供间歇性电力，因此，这种能量可以储存在电池中或通过转换为燃料是很重要的。这种储存需要将电能转换成化学能，然后再转换回来，这是由电催化剂完成的。能源转换中的许多重要反应需要昂贵的稀有金属催化剂。氢转化就是一个很好的例子。据估计，铂族金属的稀缺将严重限制(如果不是阻止)向氢经济的转换。生物非常擅长能量转换，代谢和呼吸中的许多反应都会转换能量。这些重要的反应，如氢或二氧化碳的转化，是由不依赖昂贵或稀有金属的生物催化剂(即酶)执行的。然而，这些酶中的一些存在于生物脂膜中，这些膜具有疏水性(即疏水性)，这使得在能源转换技术中使用这些类型的生物催化剂变得困难。在这个项目中，我们的目标是开发使用膜酶的新型电催化剂。我们提出的技术是基于最近的结果，这些结果表明，如果沉积在导电(金属)表面，膜酶可以用作电催化剂。在这个项目中，膜酶将与特定类型的聚合物(塑料)混合，正如我们之前证明的那样，这些聚合物可以极大地延长膜生物催化剂的寿命。最后，从细菌中分离膜酶是非常昂贵的。因此，在这个项目中，我们不会分离这些生物催化剂，而是研究如何利用细菌的粗提物，因为这将大大降低生物催化的成本。作为原理证明，我们将建造一种燃料电池，将氢和氧(空气中的氧气)转化为电能。这种氢燃料电池未来可能会为你的笔记本电脑、手机或其他移动设备充电，甚至为你的汽车充电。

It is increasingly clear that to tackle global warming and reduce our reliance on fossil fuels, a variety of approaches are required and a combination of new technologies needs to be put into practice. Many forms of renewable energy, like solar cells and windmills, provide intermittent power and hence it is important that this energy can be stored, either in batteries or by conversion into fuels. Such storage requires conversion from electrical to chemical energy and back again, which is performed by electrocatalysts. Many important reactions in energy conversion require expensive, rare metal catalysts. A case in point is hydrogen conversion. It has been estimated that the scarcity of platinum group metals will severely limit, if not prohibit, a conversion to a hydrogen economy.Biology is very adept in energy conversion and many reactions in metabolism and respiration convert energy. These important reactions, like hydrogen or carbon dioxide conversions, are performed by biocatalysts (i.e., enzymes) that do not rely on expensive or rare metals. However, some of these enzymes reside in biological lipid membranes, which are hydrophobic (i.e. water repellent) and this makes it difficult to employ these types of biocatalysts in technologies for energy conversion. In this project we aim to develop new types of electrocatalysts that use membrane enzymes. Our proposed technology is based on recent results, which show that membrane enzymes could be employed as electrocatalyst if deposited on conducting (metallic) surfaces. In this project, membrane enzymes will be mixed with specific types of polymers (plastic) as we previously demonstrated that these polymers can vastly extend the lifetime of membrane biocatalysts. Finally, isolating membranes enzymes from bacteria is very expensive. Thus, in this project we will not isolate these biocatalyst, but study how crude extracts from bacteria can be used as this will greatly reduce the cost of biocatalysis.As a proof-of-principle, we will build a fuel cell that converts hydrogen and oxygen (oxygen from air) into electricity. Such hydrogen fuel cells might, in the future, recharge your laptop, phone or other mobile devices or even power your car.