Advances in the biosynthesis of milk proteins fueled by synthetic biology

Milk proteins are ideal sources of dietary protein, characterized by excellent nutritional properties and wide applications. With the growth of the global population and changes in consumer dietary habits, there is a continuous increase in demand for sustainable and ethically produced dairy alternatives. Synthetic biology, through the design and construction of microbial cell factories, promotes the efficient biosynthesis of milk proteins while driving the green development of the dairy industry. This review first discusses the composition and content of milk proteins in milk, providing a detailed comparison of bovine and human milk. It then covers the bioactive functions of different milk proteins and their applications in industries such as food and healthcare. Finally, past research and recent advancements in milk protein biosynthesis using microbial, plant, and animal cell systems are summarized, to provide a reference for future innovations and promote sustainable bioproduction.