The ability to engineer biological systems, whether to introduce novel functionality or improved performance, is a cornerstone of biotechnology and synthetic biology. Typically, this requires the generation of genetic diversity to explore variations in phenotype, a process that can be performed at many levels, from single molecule targets (i.e., in directed evolution of enzymes) to whole organisms (e.g., in chassis engineering). Recent advances in DNA synthesis technology and automation have enhanced our ability to create variant libraries with greater control and throughput. This review highlights the latest developments in approaches to create such a hierarchy of diversity from the enzyme level to entire pathways in vitro, with a focus on the creation of combinatorial libraries that are required to navigate a target's vast design space successfully to uncover significant improvements in function.

设计生物系统的能力，无论是引入新功能还是改进性能，都是生物技术和合成生物学的基石。通常，这需要产生遗传多样性来探索表型的变化，该过程可以在多个水平上进行，从单分子目标（即，酶的定向进化）到整个生物体（例如，底盘工程）。DNA 合成技术和自动化的最新进展增强了我们创建具有更大控制力和通量的变异文库的能力。这篇综述重点介绍了创建从酶水平到体外整个途径的多样性层次结构的方法的最新进展，重点是创建组合文库，这些文库需要成功地导航目标的巨大设计空间，以发现显着的改进功能。