Heterologous expression of a new manganese-dependent peroxidase gene from Peniophora incarnata KUC8836 and its ability to remove anthracene in Saccharomyces cerevisiae

Combined induction by Cu(II) and veratrole enhances the degradation of high molecular weight polyaromatic hydrocarbons by Fusarium dlaminii ZH-H2

The effect of combined induction by Cu(II) and veratrole on the degradation of high molecular weight polyaromatic hydrocarbons (HMW-PAHs) by Fusarium sp. ZH-H2 was investigated. This strain was characterized as F. dlaminii. The combination treatment of Cu(II) with veratrole (CL) improved the degradation efficiency of a mixture of 10 HMW-PAHs by 16 % compared to the control without inducer (CK), by 5 % compared to single Cu(II) induction (C), and by 12 % compared to single veratrole induction (L). In particular, degradation of benzo(g,hi)perylene (BghiP) was improved by 36 % compared to CK and by 52 % compared to L. The CL combination treatment increased lignin peroxidase (LiP) activity by 162 % at day 5 of incubation compared to the control and by 277 % compared to C. Transcriptome analysis revealed that the expression of 910 Fusarium genes had changed as a result of the combination treatment, with 510 up-regulated genes and 443 down-regulated genes. The combined CL treatment not only significantly stimulated Lip activity, but also induced the expression of genes coding for non-ligninolytic enzymes, which contributed to the degradation of PAHs. These included cytochrome P450 monooxygenase (EC:1.-.-.-) and downstream PAH converting enzymes such as aldehyde dehydrogenase (EC:1.2.1.3), NADP-dependent ethanol dehydrogenase (EC:1.1.1.2), ethanol dehydrogenase (EC:1.1.1.156], tryptophan 2,3 dioxygenase (EC:1.13.11.52), gentisate 1,2-dioxygenase (EC:1.13.11.5), salicylate hydroxylase (EC:.14.13.1) β-hexokinase (EC:3.2.1.52), and glutathione transferase (EC: 2.5.1.18). Their increased expression enhanced the HMWPAHs degradation under induction of Cu(II) plus veratrole synergistically. These findings provide new insights in the combined use of these inducers for enhanced microbial remediation of HMW-PAHs in the environment.

Advances in the Degradation of Polycyclic Aromatic Hydrocarbons by Yeasts: A Review

Polycyclic aromatic hydrocarbons (PAHs) are toxic organic compounds produced during the incomplete combustion of organic materials and are commonly found in the environment due to anthropogenic activities such as industrial and vehicular emissions as well as natural sources, mainly volcanic eruptions and forest fires. PAHs are well known for their bioaccumulative capacity and environmental persistence, raising concerns due to their adverse effects on human health, including their carcinogenic potential. In recent years, bioremediation has emerged as a promising, effective, and sustainable solution for the degradation of PAHs in contaminated environments. In this context, yeasts have proven to be key microorganisms in the degradation of these compounds, owing to their ability to metabolize them through a series of enzymatic pathways. This review explores the advancements in yeast-mediated degradation of PAHs, with a particular focus on the role of enzymes such as cytochrome P450 (CYPs), epoxide hydrolases (EHs), and glutathione S-transferases (GSTs), which facilitate the breakdown of these compounds. The review also discusses the applications of genetic engineering to enhance the efficiency of yeasts in PAH degradation and the use of omics technologies to predict the catabolic potential of these organisms. Additionally, it examines studies addressing the degradation of benzo[a]pyrene (BaP) by yeasts such as Debaryomyces hansenii, and the potential future implications of omics sciences for developing new bioremediation.

Enhancing Manganese Peroxidase: Innovations in Genetic Modification, Screening Processes, and Sustainable Agricultural Applications

Manganese peroxidase (MnP), a vital extracellular enzyme for the degradation of lignin and other organic pollutants, has demonstrated immense potential for agricultural and environmental applications, including straw pretreatment, feed fermentation, mycotoxin degradation, and water treatment. However, current research remains in its exploratory phase, with naturally sourced MnP unable to meet industrial-scale demands and no mature commercial enzyme preparations available on the market. This comprehensive review innovatively constructs a framework for MnP research, probing into its molecular conformation and catalytic principles, while providing an overview of the advancements in high-throughput screening and In silco designing strategies. Specifically, this review focuses on the practical applications of MnP in sustainable agriculture, elaborating on its potential and challenges in straw resource utilization, efficient feed fermentation, mycotoxin control, and water quality improvement. Furthermore, this review summarizes the recent achievements in optimizing MnP activity through enzyme engineering techniques and discuss customized mutation strategies tailored to specific agricultural and environmental requirements, thereby laying a solid theoretical foundation and scientific basis for the industrial production and commercialization of MnP.

Fungal Diversity in Nam River and Their Biodegradative Activities

145 fungal isolates were obtained from three sampling sites situated within the Nam River basin, located in the southern region of South Korea. Through ITS sequence analysis, the fungal isolates were identified to comprise 55 species of ascomycetes and 11 species of basidiomycetes. The 55 species of ascomycetes exclusively belong to the phylum Pezizomycotina, comprising 33 species of Dothideomycetes, 6 species of Eurotiomycetes, and 16 species of Sordariomycetes. Regarding their plant pathogenicity, an investigation into the fungi's ability to penetrate solid media revealed Nigrospora chinensis as displaying the highest growth, followed by Pseudopestalotiopsis theae, various Curvularia species, Diaporthe species, and Alternaria alternata. Further research associating this penetration ability with fungal pathogenicity is deemed necessary. Among the 10 fungal species exhibiting penetration abilities, an examination of their capability to degrade biological polymers revealed that two strains of D. phaseolorum displayed exceptional polymer degradation. These strains exhibited remarkable abilities in decomposing malachite green and crystal violet, both recalcitrant dyes. This study underscores the potential utilization of fungal diversity in freshwater environments as a foundational approach to address freshwater pollution issues.

Textile Dye Biodecolorization by Manganese Peroxidase: A Review

Wastewater emissions from textile factories cause serious environmental problems. Manganese peroxidase (MnP) is an oxidoreductase with ligninolytic activity and is a promising biocatalyst for the biodegradation of hazardous environmental contaminants, and especially for dye wastewater decolorization. This article first summarizes the origin, crystal structure, and catalytic cycle of MnP, and then reviews the recent literature on its application to dye wastewater decolorization. In addition, the application of new technologies such as enzyme immobilization and genetic engineering that could improve the stability, durability, adaptability, and operating costs of the enzyme are highlighted. Finally, we discuss and propose future strategies to improve the performance of MnP-assisted dye decolorization in industrial applications.

A comprehensive insight into the application of white rot fungi and their lignocellulolytic enzymes in the removal of organic pollutants

Environmental problems resultant from organic pollutants are a major current challenge for modern societies. White rot fungi (WRF) are well known for their extensive organic compound degradation abilities. The unique oxidative and extracellular ligninolytic systems of WRF that exhibit low substrate specificity, enable them to display a considerable ability to transform or degrade different environmental contaminants. In recent decades, WRF and their ligninolytic enzymes have been widely applied in the removal of polycyclic aromatic hydrocarbons (PAHs), pharmaceutically active compounds (PhACs), endocrine disruptor compounds (EDCs), pesticides, synthetic dyes, and other environmental pollutants, wherein promising results have been achieved. This review focuses on advances in WRF-based bioremediation of organic pollutants over the last 10 years. We comprehensively document the application of WRF and their lignocellulolytic enzymes for removing organic pollutants. Moreover, potential problems and intriguing observations that are worthy of additional research attention are highlighted. Lastly, we discuss trends in WRF-remediation system development and avenues that should be considered to advance research in the field.

Selective delignification of poplar wood with a newly isolated white-rot basidiomycete Peniophora incarnata T-7 by submerged fermentation to enhance saccharification

BACKGROUND

Pretreatment is a critical step required for efficient conversion of woody biomass into biofuels and platform chemicals. Fungal pretreatment is regarded as one of the most promising technology for woody biomass conversion but remains challenging for industrial application. The exploration of potential fungus strain with high efficient delignification and less processing time for woody biomass pretreatment will be valuable for development of biorefinery industry. Here, a newly isolated white-rot basidiomycete Peniophora incarnate T-7 was employed for poplar wood pretreatment.

RESULTS

The chemical component analysis showed that cellulose, hemicellulose and lignin from poplar wood declined by 16%, 48% and 70%, respectively, after 7 days submerged fermentation by P. incarnate T-7. Enzymatic saccharification analysis revealed that the maximum yields of glucose and xylose from 7 days of P. incarnate T-7 treated poplar wood reached 33.4% and 27.6%, respectively, both of which were enhanced by sevenfold relative to the untreated group. Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), X-ray diffraction (XRD) and pyrolysis gas chromatography-mass spectrometry (Py-GC/MS) characterization confirmed that lignocellulosic structure of poplar wood was largely broken by P. incarnate T-7, including delignification and de-crystalline of cellulose. Meanwhile, lignin component of poplar wood was selectively degraded by P. incarnate T-7, and G-type unit of lignin was preferentially attacked by the strain. Furthermore, quantitative proteomic analysis revealed that a considerable amount of lignocellulolytic enzymes were detected in the secretory proteins of P. incarnate T-7, especially with high abundance of lignin-degrading enzymes and hemicellulases. Combination of quantitative proteomic with transcriptomic analysis results showed that most of those lignocellulolytic enzymes were highly upregulated on poplar wood substrate compared to glucose substrate.

CONCLUSIONS

This study showed that P. incarnate T-7 could selectively delignify poplar wood by submerged fermentation with short time of 7 days, which greatly improved its enzymatic saccharification efficiency. Our results suggested that P. incarnate T-7 might be a promising candidate for industrial woody biomass pretreatment.

Contemporary enzyme based technologies for bioremediation: A review

The persistent disposal of xenobiotic compounds like insecticides, pesticides, fertilizers, plastics and other hydrocarbon containing substances is the major source of environmental pollution which needs to be eliminated. Many contemporary remediation methods such as physical, chemical and biological are currently being used, but they are not sufficient to clean the environment. The enzyme based bioremediation is an easy, quick, eco-friendly and socially acceptable approach used for the bioremediation of these recalcitrant xenobiotic compounds from the natural environment. Several microbial enzymes with bioremediation capability have been isolated and characterized from different natural sources, but less production of such enzymes is a limiting their further exploitation. The genetic engineering approach has the potential to get large amount of recombinant enzymes. Along with this, enzyme immobilization techniques can boost the half-life, stability and activity of enzymes at a significant level. Recently, nanozymes may offer the potential bioremediation ability towards a broad range of pollutants. In the present review, we have described a brief overview of the microbial enzymes, different enzymes techniques (genetic engineering and immobilization of enzymes) and nanozymes involved in bioremediation of toxic, carcinogenic and hazardous environmental pollutants.