Improved reference quality genome sequence of the plastic-degrading greater wax moth, Galleria mellonella

Abstract

Galleria mellonella is a pest of honeybees in many countries because its larvae feed on beeswax. However, G. mellonella larvae can also eat various plastics, including polyethylene, polystyrene and polypropylene, so the species is garnering increasing interest as a tool for plastic biodegradation research. This paper presents an improved genome (99.3% completed lepidoptera_odb10 BUSCO; genome mode) for G. mellonella. This 472 Mb genome is in 221 contigs with an N50 of 6.4 MB and contains 13,604 protein-coding genes. Genes that code for known and putative polyethylene-degrading enzymes and their similarity to proteins found in other Lepidoptera are highlighted. An analysis of secretory proteins more likely to be involved in the plastic catabolic process has also been carried out.

Nature’s Plastic Predators: A Comprehensive and Bibliometric Review of Plastivore Insects

“…This is evident by the fact that, the only insect-origin enzymes characterized for plastic degradation are four hexamerin proteins reported in the greater wax moth in 2022, named; Demetra, Ceres, Cora and Cibeles [ 49 ]. These enzymes are oxidases in nature and have been shown to possess promiscuous array of functions, thus adding more evidence to neofunctionalisation of enzymes [ 22 ]. The enzymes responsible for the plastic degradation capabilities of the rest of insects remains to be identified, thus making this a high potential field of research.…”

“…Despite limitations in biodegradation abilities, computational approaches offer promise for the accelerated evolution of plastic-degrading enzymes. Comparative genomics studies, like those on the greater wax moth, reveal the repurposing of enzyme families for plastic degradation [ 20 , 22 ] suggesting exaptation, rather than traditional evolution, as the dominant mechanism behind plastic-degrading enzymes. Further studies are crucial for enhancing the capabilities of insects and their enzymes in biodegrading plastics, potentially rendering insects invaluable allies in combating plastic waste.…”

“…As higher organisms demonstrating plastic consumption abilities, insects remain poorly understood in terms of the enzymes and mechanisms underlying this ability. This review aims to consolidate current knowledge on insect plastic degradation while also identifying avenues for future research, such as elucidating the potential neofunctionalised pathways involved related to natural polymers digestion [ 18 , 22 ].…”