AMPed

Antimicrobial resistance is a global phenomenon arising from the indiscriminate use of antibiotics. To combat this problem, the Antimicrobial Peptide Cecropin B (CecB), a highly-effective, broad-spectrum antibiotic alternative is expressed in transgenic Chlorella autotrophica, a well-studied and highly-productive protein expressing microalgal chassis. It is expressed with a secretion signal peptide for extraction; and SUMO-tag for in-vitro cleavage using SUMO-protease. To validate efficacy, the isolated CecB is tested against common aquatic pathogens. The in-vitro cleavage system, barring the signal peptide, is also expressed using a bacterial chassis. This is to test the design and quantify the differences between microalgal and bacterial synthetic capabilities. To modify the system for industrial use, the signal peptide is removed and the SUMO-protease is additionally inserted, under a nitrogen-starvation inducible promoter, to cleave SUMO in-vivo and generate active AMPs. The microalgae are then freeze-dried, preserving active AMPs internally, which can then be used as supplemental feed.