UC San Diego

Micro algae are a sustainable alternative energy feed sock for fossil fuels. One of the major challenges of producing biofuel from micro algae is the harvesting of micro algae. There are many techniques for harvesting micro algae, but most techniques are too expensive to compete with fossil fuel production costs. One low cost harvesting technique is flocculation, but current flocculation agents are not sustainable for large- scale production. We engineered a sustainable and scalable E. coli bioflocculation agent that uses all four coagulation mechanisms to bioflocculate the micro algae C. reinhardtii. We expressed bioflocculating and self-aggregating peptides on an E. coli display system to harvest C. reinhardtii. We incorporated all four coagulation mechanisms in the design of the E. coli surface displayed peptides and created a positively charged, self- aggregating E. coli net that sweeps the water column, entrapping the micro algae C. reinhardtii.