Abstract:Enzymes and cell factories are the core of industrial biotechnology. They play important roles in various fields such as medicine, chemical industry, food, agriculture, and energy. Usually, natural enzymes and cells need to be engineered to improve the catalytic efficiency, stability and enantioselectivity. Directed evolution makes it possible to rapidly improve the properties of enzymes and cell factories. Sensitive and reliable high-throughput screening approaches are the key for successful and efficient engineering of enzymes and cell factories. In this review, we first summarize the advantages and disadvantages of different screening methods and signal generation strategies as well as their application scope; we then describe the latest advances of ultra-high throughput screening technology applied in the directed evolution of enzymes and cell factories in the past three years. On this basis, we discuss the limiting factors that need to be further improved for high-throughput screening systems and forecast the future development trends of high-throughput screening methods, hoping that researchers in various fields including biotechnology and instrument development can cooperate closely to enhance the reliability and applicability of the high-throughput screening techniques.