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Recently, the artificial starch research team at the Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, developed a low-carbon yeast cell starch synthesis route using acetic acid as a raw material, achieving efficient low-carbon microbial synthesis of starch; the relevant findings were published in Nature Communications. It is said that starch, as the main carbohydrate, is an important raw material for food as well as a key raw material for industry. By optimizing the expression level of the heterologous starch synthesis pathway, precisely regulating the gluconeogenesis and starch catabolism pathways, and employing engineering strategies such as morphological engineering to increase the internal space for starch storage, the researchers systematically overcame the bottleneck of insufficient starch synthesis capacity in yeast’s natural metabolic network. Using acetic acid synthesized by electroreduction of carbon dioxide as a raw material, they achieved a starch content of 47.18% of the cell dry weight, a space-time production efficiency of 243.7 grams per square meter per day, and a production intensity of 160.9 milligrams per liter per hour – values that are one order of magnitude higher than those of other microorganisms. This research reveals systematically new mechanisms by which the cellular resource allocation network is restructured to support high-level starch synthesis. Through strain engineering that combines metabolic regulation with pathway optimization, it was possible to regulate the starch composition and the starch-protein ratio in yeast cells used to produce artificial micro-grains, demonstrating the great potential of applying engineering biotechnology to customize the composition of functional nutritional ingredients and to develop ideal foods and feeds.