Biocatalysis, the use of enzymes in chemical transformations, is an important green chemistry tool. Cascade reactions combine different enzyme activities in a sequential set of reactions. Cascades can occur within a living (usually bacterial) cell; in vitro in 'one pot' systems where the desired enzymes are mixed together to carry out the multi-enzyme reaction; or using microfluidic systems. Microfluidics offers particular advantages when the product of the reaction inhibits the enzyme(s). In vitro systems allow variation of different enzyme concentrations to optimise the metabolic 'flux', and the addition of enzyme cofactors as required. Cascades including cofactor recycling systems and modelling approaches are being developed to optimise cascades for wider industrial scale use. Two industrially important enzymes, transaminases and carboxylic acid reductases are used as examples regarding their applications in cascade reactions with other enzyme classes to obtain important synthons of pharmaceutical interest.

中文翻译：

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在生物催化中使用级联酶：重点介绍转氨酶和羧酸还原酶。

生物催化是酶在化学转化中的应用，是一种重要的绿色化学工具。级联反应在一系列反应中结合了不同的酶活性。级联可以发生在活的（通常是细菌的）细胞内。在“一锅”系统中进行体外，将所需的酶混合在一起以进行多酶反应；或使用微流体系统。当反应产物抑制酶时，微流体技术具有特别的优势。体外系统允许不同酶浓度的变化以优化代谢“通量”，并根据需要添加酶辅因子。正在开发包括辅因子回收系统和建模方法的级联，以优化级联，以更广泛地用于工业规模。两种工业上重要的酶，