Mutations of esterase 3 confer two forms of organophosphate resistance on contemporary Australasian Lucilia cuprina . One form, called diazinon resistance, is slightly more effective against commonly used insecticides and is now more prevalent than the other form, called malathion resistance. We report here that the single amino acid replacement associated with diazinon resistance and two replacements associated with malathion resistance also occur in esterase 3 in the sibling species Lucilia sericata , suggesting convergent evolution around a finite set of resistance options. We also find parallels between the species in the geographic distributions of the polymorphisms: In both cases, the diazinon-resistance change is absent or rare outside Australasia where insecticide pressure is lower, whereas the changes associated with malathion resistance are widespread. Furthermore, PCR analysis of pinned specimens of Australasian L. cuprina collected before the release of organophosphate insecticides reveals no cases of the diazinon-resistance change but several cases of those associated with malathion resistance. Thus, the early outbreak of resistance in this species can be explained by the preexistence of mutant alleles encoding malathion resistance. The pinned specimen analysis also shows much higher genetic diversity at the locus before organophosphate use, suggesting that the subsequent sweep of diazinon resistance in Australasia has compromised the scope for the locus to respond further to the ongoing challenge of the insecticides.

Neonicotinoids are neurotoxic systemic insecticides used in plant protection worldwide. Unfortunately, application of neonicotinoids affects both beneficial and target insects indiscriminately. Being water soluble and persistent, these pesticides are capable of disrupting both food chains and biogeochemical cycles. This review focuses on the biodegradation of neonicotinoids in soil and water systems by the bacterial community. Several bacterial strains have been isolated and identified as capable of transforming neonicotinoids in the presence of an additional carbon source. Environmental parameters have been established for accelerated transformation in some of these strains. Studies have also indicated that enhanced biotransformation of these pesticides can be accomplished by mixed microbial populations under optimised environmental conditions. Substantial research into the identification of neonicotinoid-mineralising bacterial strains and identification of the genes and enzymes responsible for neonicotinoid degradation is still required to complete the understanding of microbial biodegradation pathways, and advance bioremediation efforts.

The genus Trichoderma is widely recognized for its ability to secrete lignocellulosic enzymes, establishing it as a crucial technological resource for the bioconversion of agro-industrial waste biomass via fermentation. This review explores the potential of utilizing lignocellulosic waste from diverse industries as a sustainable nutrient source for producing Trichoderma spp. and various desirable metabolites via fermentation. Significant emphasis is placed on the enzymatic activities of Trichoderma species in two critical stages of second-generation biofuel production. Firstly, in the pre-treatment stage to break down complex polysaccharides of lignocellulosic biomass, thereby enhancing production efficiency and yield, and, secondly, during the hydrolysis process to produce fermentable sugars essential for biofuel production. Additionally, this review discusses other applications of Trichoderma fermentation, such as enhancing animal feedstock nutrition and employing its spores as biocontrol agents. Ongoing research efforts are directed at optimizing fermentation protocols, identifying suitable waste substrates, and genetic manipulation of strains to enhance the economic viability of Trichoderma’s biotechnological applications. This manuscript contributes to the field of circular biotechnology by offering a detailed review of recent progress on the integration of agro-industrial waste materials in Trichoderma-based bioconversion technologies, highlighting both current achievements and future research directions necessary to enhance the economic and environmental sustainability of waste biomass utilization.

The asymmetric reduction of enoates, imines and ketones are among the most important reactions in biocatalysis. These reactions are routinely conducted using enzymes that use nicotinamide cofactors as reductants. The deazaflavin cofactor F₄₂₀ also has electrochemical properties that make it suitable as an alternative to nicotinamide cofactors for use in asymmetric reduction reactions. However, cofactor F₄₂₀-dependent enzymes remain under-explored as a resource for biocatalysis. This review considers the cofactor F₄₂₀-dependent enzyme families with the greatest potential for the discovery of new biocatalysts: the flavin/deazaflavin-dependent oxidoreductases (FDORs) and the luciferase-like hydride transferases (LLHTs). The characterized F₄₂₀-dependent reductions that have the potential for adaptation for biocatalysis are discussed, and the enzymes best suited for use in the reduction of oxidized cofactor F₄₂₀ to allow cofactor recycling in situ are considered. Further discussed are the recent advances in the production of cofactor F₄₂₀ and its functional analog F_O-5′-phosphate, which remains an impediment to the adoption of this family of enzymes for industrial biocatalytic processes. Finally, the prospects for the use of this cofactor and dependent enzymes as a resource for industrial biocatalysis are discussed.