AUTHOR=Meng Weizhao , Xia Mengsheng , Hu Jingyan , Wang Chao , Qian Cheng , Zhang Mingmin , Fu Weiqi TITLE=Adaptation and synthetic biology of the model cyanobacterium Synechococcus elongatus for sustainable development: a review JOURNAL=Frontiers in Marine Science VOLUME=Volume 12 - 2025 YEAR=2025 URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2025.1542670 DOI=10.3389/fmars.2025.1542670 ISSN=2296-7745 ABSTRACT=Synechococcus elongatus is a model cyanobacterium with remarkable adaptability to diverse environmental stresses, making it a promising candidate for the photoautotrophic conversion of carbon dioxide into valuable chemicals. This review explores the adaptive mechanisms that allow S. elongatus to survive under various abiotic stresses, such as changes in CO2 levels, heavy metals, and light conditions. We also highlight recent advancements in synthetic biology that have enabled the engineering of S. elongatus to produce biofuels and other value-added compounds, including fatty acids, alcohols, and carotenoids. Additionally, we discuss the applications of modern omics techniques to elucidate the genetic basis of stress tolerance and metabolic regulation. Despite the promising potential of S. elongatus for industrial applications, challenges remain in scaling up production, enhancing genetic stability, and optimizing bioreactor systems. Finally, we provide insights into future directions, including the integration of genome engineering, system-level modeling, and co-culture strategies, to improve the efficiency of cyanobacterial cell factories for sustainable biotechnology applications.