The marine diatom Phaeodactylum tricornutum as a versatile bioproduction chassis: Current progress, challenges and perspectives.

Beyond its importance in diatom studies, the marine model diatom Phaeodactylum tricornutum has emerged as a versatile photosynthetic chassis for sustainable bioproduction, leveraging both native bioactive metabolites and engineered heterologous compounds through synthetic biology. Over the past three decades, transformative advances in genetic tool development, including transgenic element optimization, CRISPR/Cas genome editing and high-efficiency transformation systems, have driven strain engineering for elevated fucoxanthin, fatty acid, triacylglycerol yields and successful synthesis of diverse heterologous products, from terpenoids and therapeutic peptides to sustainable materials. Concurrently, advances in molecular toolkits have refined chassis optimization by elucidating fundamental biological mechanisms underlying nutrient uptake, environmental stress adaptation, stimuli sensing and cell development. Despite the progress, critical challenges persist, particularly suboptimal product yield, biomass limitations as well as a prohibitive production cost which hinder industrial translation. This review examines emerging strategies, such as chloroplastic gene expression, DNA site-specific integration and trophic alteration, promising for species improvement, while addressing other scale-up considerations including cultivation strategies, techno-economic analysis and regulatory policies. The integrative efforts could accelerate the transition of P. tricornutum from a model diatom to a scalable, eco-friendly biomanufacturing platform.