Engineered algae are a bioremediation triple threat, synergizing microplastic removal, upcycling and wastewater nutrient utilization to combat environmental contamination. By genetically engineering cyanobacteria to produce limonene, researchers from the University of Missouri (MO, USA) and Texas A&M University (TX, USA) have created a system that could be used to remove microplastics from wastewater. With refinement, this approach could one day be used for bioremediation and upcycling efforts to help tackle our environmental pollution problem. Microplastics pose a major threat to ecosystems, with negative impacts on a broad spectrum of living organisms, including microbes, plants, animals and humans. Their removal from the environment requires efficient, cost-effective and sustainable remediation strategies – however these are hard to come by. Conventional methods are expensive and often subject to clogging and water chemistry variations that impact their effectiveness. Meanwhile, current state-of-the-art remediation primarily focuses on designing systems to remove microplastics from the aqueous phase, which leaves a waste stream that requires storage or further processing. Moreover, microplastic removal capacity generally decreases when particle sizes get smaller – all of which means we are in need of new and improved microplastic remediation technologies if we are to curb its environmental contamination. It is against this backdrop that scientists have developed RUMBA – a technology for the remediation and upcycling of microplastics by algae. The team engineered Synechococcus elongatus UTEX 2973 to produce limonene – the chemical that gives oranges their zesty scent – which is enriched on the cell surface, increasing hydrophobicity. This, in turn,…