Phaeodactylum tricornutum as a Chassis: Insights into Its Potential, Challenges, and Perspectives

<i>Phaeodactylum tricornutum</i> is one of the most well-characterized microalgae and serves as a pivotal model diatom in global carbon fixation and the mediation of biogeochemical cycling of essential nutrients. Over the past few decades, the availability of a complete genome assembly, coupled with the development of robust DNA manipulation tools and efficient DNA delivery methodologies, has established <i>P. tricornutum</i> as a promising photosynthetic chassis for the sustainable bioproduction of high-value compounds, including fucoxanthin and eicosapentaenoic acid (EPA). This review systematically summarizes the research progress in the strain improvement toolkit of <i>P. tricornutum</i>, encompassing both genetic and non-genetic engineering strategies. It elaborates on the types and applications of its representative bioactive products, as well as the molecular mechanisms underlying key synthetic pathways. Additionally, this work synthesizes the research findings on the optimization of critical cultivation conditions (e.g., light, temperature, and nutrient composition) that modulate the growth and product synthesis of <i>P. tricornutum</i>. On this basis, the challenges encountered by <i>P. tricornutum</i> in industrial applications are proposed for further discussion, aiming to provide a reference for in-depth exploration of related research directions and facilitate the expansion of its application scope in the field of biomanufacturing.