https://video.igem.org/videos/watch/fdcba89b-69ab-4844-8c59-0aee16cf39ca Title: MelanoShield: Melanin-Protected Bt Cry1Ac for Sustainable Control of Lepidopteran Pests Description: The diamondback moth (Plutella xylostella), a major cruciferous pest, causes USD 4–5 billion in annual global losses. While Bt biopesticides are environmentally friendly alternatives to chemical pesticides, their broad use is constrained by unstable efficacy under UV irradiation and total field usage costs. To tackle these constraints, we developed MelanoShield, integrating UV shielding for Bt Cry1Ac and toxin-delivery engineering, together with two hardware prototypes to increase field application efficiency. Using E. coli W3110(DE3), we built a melanin–Cry1Ac co-production system yielding 1.80 g/L melanin with tyrosine feeding; 0.05 g/L melanin blocked 95.4% of UV light. We engineered an SmChiA–Cry1Ac fusion construct to facilitate toxin penetration through the insect peritrophic matrix via linker optimization (expression optimization ongoing). Separately, we designed an ESM-2 protein engineering workflow that identified MelA W144K, which increased the titer by 14.5% over wild type (from 0.55 ± 0.04 g/L to 0.63 ± 0.03 g/L). Wiki | Official Page Thu, 29 Oct 2026 22:23:41 GMT https://validator.w3.org/feed/docs/rss2.html PeerTube - https://video.igem.org https://video.igem.org/client/assets/images/icons/icon-1500x1500.png https://video.igem.org/videos/watch/fdcba89b-69ab-4844-8c59-0aee16cf39ca All rights reserved, unless otherwise specified in the terms specified at https://video.igem.org/about and potential licenses granted by each content's rightholder.