An attacin antimicrobial peptide, Hill_BB_C10074, from Hermetia illucens with anti-Pseudomonas aeruginosa activity

Abstract

Background There is a global need to develop new therapies to treat infectious diseases and tackle the rise in antimicrobial resistance. To date, the larvae of the Black Solider Fly, Hermetia illucens, have the largest repertoire of antimicrobial peptides derived from insects. Antimicrobial peptides are of particular interest in the exploration of alternative antimicrobials due to their potent action and reduced propensity to induce resistance compared with more traditional antibiotics. Results The predicted attacin from H. illucens, Hill_BB_C10074, was first identified in the transcriptome of H. illucens populations that had been fed a plant-oil based diet. In this study, recombinant Hill_BB_C10074 (500 µg/mL), was found to possess potent antimicrobial activity against the serious Gram-negative pathogen, Pseudomonas aeruginosa. Sequence and structural homology modelling predicted that Hill_BB_C10074 formed a homotrimeric complex that may form pores in the Gram-negative bacterial outer membrane. In vitro experiments defined the antimicrobial action of Hill_BB_C10074 against P. aeruginosa and transmission electron microscopy and electrochemical impedance spectroscopy confirmed the outer membrane disruptive power of Hill_BB_C10074 which was greater than the clinically relevant antibiotic, polymyxin B. Conclusions Combining predictive tools with in vitro approaches, we have characterised Hill_BB_C10074 as an important insect antimicrobial peptide and promising candidate for the future development of clinical antimicrobials.

A novel family of defensin-like peptides from Hermetia illucens with antibacterial properties

“…The larvae reside in large colonies that feed on decaying material such as animal and plant wastes [ 24 ]. The species is of growing interest in industrial and research sectors engaged in the bioeconomical production of food, the bioremedial management of waste, and the development of novel therapeutics [ 25 – 27 ].…”

“…Bioinformatic analysis of the BSFL genome has identified 57 putatively active AMPs [ 13 ]. To date, 17 AMPs from H. illucens have been characterised for their in vitro antimicrobial activity against bacteria [ 21 , 25 , 30 – 36 ]. Hidefensin-1 and Hidiptericin-1 inhibit the growth of Streptococcus pneumoniae and Escherichia coli , while HiCG13551 inhibits the growth of S. aureus and E. coli [ 21 ].…”