Engineering Enzymes for Pharmaceutical Amide Synthesis

酰胺键是药物化学中最重要的键之一，在许多治疗溃疡、高胆固醇和细菌和病毒致病性感染的重要日常药物中发挥着重要作用。因此，寻找原子高效、可持续的绿色合成药物酰胺的化学方法至关重要。然而，用于制备酰胺的工业合成方法受到使用复杂或危险试剂来完成其化学反应并产生大量废物的影响。由于缺乏效率，工业合成化学家越来越多地转向“生物催化”或“工业生物技术”作为合成药物生产分子的首选方法。生物催化剂，如酶或微生物，通常以优异的原子效率和选择性实现化学键的合成，自然也擅长合成酰胺键，这是将蛋白质结构结合在一起的主要键。然而，到目前为止，用于形成酰胺键的生物催化剂在工业应用中很少受到关注，尽管这种酶反应是许多化学家寻找生物催化解决合成问题的首选。这是因为自然界中酰胺键形成的生物催化方法虽然有效，但往往很复杂，很难应用于自然环境之外。在本项目中，我们建议深入研究酰胺键形成新酶的合成潜力，并利用这些酶合成含酰胺的药物化合物。我们将使用合成化学和生物催化的混合物来定义新酶的潜力和局限性。然后，我们将使用x射线晶体学解决酶的结构，并使用合理的酶重新设计来扩大酶的潜力，以催化合成更广泛的药学相关分子。

The amide bond is one of the most significant in pharmaceutical chemistry, featuring in a host of important everyday pharmaceuticals for the treatment of ulcers, high cholesterol and pathogenic infections by bacteria and viruses. It is vital therefore that there exist atom efficient and sustainable green chemical methods for the synthesis of pharmaceutical amides. However, industrial synthetic methods for the preparation of amides suffer from the use of complex or hazardous reagents to accomplish their chemistry and generate a large amount of waste. Because of this lack of efficiency, industrial synthetic chemists are increasingly turning towards 'biocatalysis' or 'Industrial Biotechnology' as the preferred method of synthesising molecules for pharmaceutical production. Biocatalysts, such as enzyme or microbes, typically achieve the synthesis of chemical bonds with excellent atom efficiency and selectivity, and Nature is also expert at synthesising amide bonds, which are the major bonds that hold the structure of proteins together. Until now however, biocatalysts for the formation of amide bonds have received little attention for industrial application, even though such enzyme reactions feature at the top of the list for many chemists looking for biocatalytic solutions to synthetic problems. This is because biocatalytic methods for amide bond formation in Nature, while efficient, are often complex, and difficult to apply out of their natural context. In this project we propose to thoroughly investigate the synthetic potential of new enzymes for amide bond formation, and to use these to synthesise amide-containing pharmaceutical compounds. We will define the potential and limitations of new enzymes using a mixture of synthetic chemistry and biocatalysis. We will then solve the structures of the enzymes using X-ray crystallography and use rational enzyme redesign to expand their potential of the enzymes to catalyse the synthesis of a wider range of pharmaceutically relevant molecules.