ABSTRACTThe larvae of the common green bottle fly (Lucilia sericata) produce antibacterial secretions that have a therapeutic effect on chronic and nonhealing wounds. Recent developments in insect biotechnology have made it possible to use these larvae as a source of novel anti-infectives. Here, we report the application of next-generation RNA sequencing (RNA-Seq) to characterize the transcriptomes of the larval glands, crop, and gut, which contribute to the synthesis of antimicrobial peptides (AMPs) and proteins secreted into wounds. Our data confirm thatL. sericatalarvae have adapted in order to colonize microbially contaminated habitats, such as carrion and necrotic wounds, and are protected against infection by a diverse spectrum of AMPs.L. sericataAMPs include not only lucifensin and lucimycin but also novel attacins, cecropins, diptericins, proline-rich peptides, and sarcotoxins. We identified 47 genes encoding putative AMPs and produced 23 as synthetic analogs, among which some displayed activities against a broad spectrum of microbial pathogens, includingPseudomonas aeruginosa,Proteus vulgaris, andEnterococcus faecalis. AgainstEscherichia coli(Gram negative) andMicrococcus luteus(Gram positive), we found mostly additive effects but also synergistic activity when selected AMPs were tested in combination. The AMPs that are easy to synthesize are currently being produced in bulk to allow their evaluation as novel anti-infectives that can be formulated in hydrogels to produce therapeutic wound dressings and adhesive bandages.
Genome and transcriptome sequencing of the green bottle fly, Lucilia sericata, reveals underlying factors of sheep flystrike and maggot debridement therapy
