In silico study for investigating plastic-biodegrading enzyme sequences in the genome of the insect Galleria mellonella

Abstract

Plastics are widely utilized due to their versatility and durability. However, their accumulation poses a significant negative impact on the environment. The biodegradation of plastics is a slow process driven by abiotic factors and microbial enzymes. Studies have demonstrated that the larvae of the insect Galleria mellonella L. (Linnaeus 1758) biodegrade plastics at a rate exceeding that of microbial biodegradation. Nevertheless, the enzymes involved in plastic biodegradation within the larvae remain poorly studied. Given the availability of the G. mellonella genome in public databases, this study aimed to identify enzyme sequences in the insect’s genome that are homologous to microbial enzymes known for their roles in plastic biodegradation. A total of 40 microbial enzyme sequences were selected from the literature and compared with the G. mellonella genome. Four insect enzymes were further analyzed through molecular modeling and docking to examine their three-dimensional structures, catalytic regions, and interactions with substrates. Notably, two esterases, FE4-like isoform X2 and FE4-like, were identified as candidates for biodegrading BHET and PU. To date, no esterase from G. mellonella has been reported as being active in plastic biodegradation. This study represents pioneering research employing bioinformatics approaches to uncover enzyme sequences in the genome of G. mellonella associated with plastic biodegradation.