[Upgrading microbial strains for fermentation industry].

Fermentation is a green, low-carbon and sustainable process for the production of food, chemicals, fuels, and materials by using microbial strains as biocatalysts and renewable resources such as starch and biomass as feedstocks. China has the world's largest fermentation industry, the scale of amino acids, vitamins, and some other fermentation products accounted for 60%-80% of the global market share. The development of fermentation industry is of great significance for the strategic goal of "carbon neutralization and carbon peak" and the development of bioeconomy. Microbial strains are the core of fermentation industry, which directly decide what kind of chemical can be produced from what kind of feedstock at what cost. Innovating industrial strains to improve the conversion efficiency of raw materials, increase the production level, and expand product portfolio is the key to the high-quality development of fermentation industry. In recent years, the development of synthetic biology and systems biology has further deepened the understanding of the physiological and metabolic mechanisms of microbial chassis and accelerated the development of gene editing and other enabling technologies for strain design and engineering. All these advances have provided new driving force for the upgrading of industrial strains. This review focused on the representative fermentation products including amino acids, B vitamins, citric acid, and bio-ethanol. The latest progress of strain development for fermentation industry was reviewed from the perspective of basic research and technology innovation for industrial microbial chassis. How the integration of artificial intelligence and automation with life science will reshape the upgrading of industrial strains was also discussed.