Proteomic analysis of the response of Rhizopus oryzae ENHE to pentachlorophenol: Understanding the mechanisms for tolerance and degradation of this toxic compound

Proteomics insights into the fungal-mediated bioremediation of environmental contaminants

As anthropogenic activities continue to introduce various contaminants into the environment, the need for effective monitoring and bioremediation strategies is critical. Fungi, with their diverse enzymatic arsenal, offer promising solutions for the biotransformation of many pollutants. While conventional research reports on ligninolytic, oxidoreductive, and cytochrome P450 (CYP) enzymes, the vast potential of fungi, with approximately 10 345 protein sequences per species, remains largely untapped. This review describes recent advancements in fungal proteomics instruments as well as software and highlights their detoxification mechanisms and biochemical pathways. Additionally, it highlights lesser-known fungal enzymes with potential applications in environmental biotechnology. By reviewing the benefits and challenges associated with proteomics tools, we hope to summarize and promote the studies of fungi and fungal proteins relevant in the environment.

A promising alternative for sustainable remediation of carbendazim in aquatic environments

The treatment of carbendazim-contaminated effluents is a challenge because of its complex composition and toxicity. A promising solution lies in biodegradation and the fungus Actinomucor elegans LBM 290 shows significant potential in this regard. Thus, the aim of this study was to biodegrade MBC by A. elegans LBM 290 in a liquid medium addressing the changes in the fungal morphology and protein production. The fungus A. elegans LBM 290 efficiently remove the fungicide carbendazim, with 86.6% removal within 8 days. This degradation is a combination of biodegradation (24.54%) and adsorption (62.08%). Exposure to carbendazim negatively affected the fungus, causing a decrease in biomass and morphological changes. Proteomic analysis revealed the fungal response to carbendazim stress through increased production of Cu-Zn superoxide dismutase, an antioxidant enzyme that combats oxidative stress, and the presence of a G protein subunit, suggesting participation in stress signaling pathways. These findings contribute to understanding the strategies of A. elegans LBM 290 to cope with carbendazim exposure in aquatic environments.

Antifungal activity and mechanism of electron beam irradiation against Rhizopus oryzae

Electron beam irradiation is a physical fungicidal technique that has emerged as a potential application in China. However, its antifungal activity and mechanism against Rhizopus oryzae have not been reported. Thus, this study aimed to investigate the antifungal activity and mechanism of electron beam irradiation of R. oryzae. The antifungal activity analysis showed that the D₁₀ value and complete elimination dose of R. oryzae irradiated by electron beam were 1.73 kGy and 8.08 kGy, respectively. Electron beam irradiation has a strong inhibitory effect on the filamentous biomass of R. oryzae. To reveal the antifungal mechanism of electron beam against R. oryzae, this study analyzed the dynamic changes in the cell wall, cell membrane, and oxidative stress induced by different irradiation doses. The results showed that electron beam irradiation destroyed the cell wall structure of R. oryzae, increasing chitinase activity and decreasing chitin content. Cell membrane integrity is disrupted, increasing relative conductivity, decreasing pH values, and decreasing soluble protein content. Electron beam irradiation causes oxidative stress in cells, increasing H₂O₂ content, decreasing antisuperoxide anion activity, decreasing DPPH free radical scavenging activity, and inhibiting defense enzyme (CAT and SOD) activity. This phenomenon indicates that electron beams can cause structural damage to and metabolic dysfunction of cells and disorders of redox homeostasis, which may be the main cause of growth inhibition and cell death in R. oryzae.

Myco-remediation of Chlorinated Pesticides: Insights Into Fungal Metabolic System

Synthetic chemicals including organochlorine pesticides pose environment and health hazard due to persistent and bio-accumulation property. Majority of them are recognized as endocrine disruptors. Fungi are ubiquitous in nature and employs efficient enzymatic machinery for the biotransformation and degradation of toxic, recalcitrant pollutants. This review critically discusses the organochlorine biotransformation process mediated by fungi and highlights the role of enzymatic system responsible for biotransformation, especially distribution of dehalogenase homologs among fungal classes. It also explores the potential use of fungal derived biomaterial, mainly chitosan as an adsorbing biomaterial for pesticides and heavy metals removal. Further, prospects of employing fungus to over-come the existing bioremediation limitations are discussed. The study highlights the potential scope of utilizing fungi for initial biotransformation purposes, preceding final biodegradation by bacterial species under environmental conditions.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12088-021-00940-8.