In this study, we conducted an extensive investigation of the biodegradation capabilities and stress response of the newly isolated strain Pseudomonas veronii SM-20 in order, to assess its potential for bioremediation of sites contaminated with polycyclic aromatic hydrocarbons (PAHs). Initially, phenotype microarray technology demonstrated the strain's proficiency in utilizing various carbon sources and its resistance to certain stressors. Genomic analysis has identified numerous genes involved in aromatic hydrocarbon metabolism. Biodegradation assay analyzed the depletion of phenanthrene (PHE) when it was added as a sole carbon and energy source. We found that P. veronii strain SM-20 degraded approximately 25% of PHE over a 30-day period, starting with an initial concentration of 600 µg/mL, while being utilized for growth. The degradation process involved PHE oxidation to an unstable arene oxide and 9,10-phenanthrenequinone, followed by ring-cleavage. Comparative proteomics provided a comprehensive understanding of how the entire proteome responded to PHE exposure, revealing the strain's adaptation in terms of aromatic metabolism, surface properties, and defense mechanism. In conclusion, our findings shed light on the promising attributes of P. veronii SM-20 and offer valuable insights for the use of P. veronii species in environmental restoration efforts targeting PAH-impacted sites.

• Keywords
• Pseudomonas, biodegradation, genomics, phenanthrene (PHE), polycyclic aromatic hydrocarbons (PAHs), proteomics,
• Publication type
• Journal Article MeSH

Long-term exposure to polycyclic aromatic hydrocarbons (PAHs) and their nitrated (NPAHs) and oxygenated (OPAHs) derivatives can cause adverse health effects due to their carcinogenicity, mutagenicity and oxidative potential. The distribution of PAH derivatives in the terrestrial environment has hardly been studied, although several PAH derivatives are ubiquitous in air and long-lived in soil and water. We report the multi-annual variations in the concentrations of NPAHs, OPAHs and PAHs in soils sampled at a semi-urban (Mokrá, Czech Republic) and a regional background site (Košetice, Czech Republic) in central Europe. The concentrations of the Σ18NPAHs and the Σ11+2OPAHs and O-heterocycles were 0.31 ± 0.23 ng g-1 and 4.03 ± 3.03 ng g-1, respectively, in Košetice, while slightly higher concentrations of 0.54 ± 0.45 ng g-1 and 5.91 ± 0.45 ng g-1, respectively, were found in soil from Mokrá. Among the 5 NPAHs found in the soils, 1-nitropyrene and less so 6-nitrobenzo(a)pyrene were most abundant. The OPAHs were more evenly distributed. The ratios of the PAH derivatives to their parent PAHs in Košetice indicate that they were long-range transported to the background site. Our results show that several NPAHs and OPAHs are abundant in soil and that gas-particle partitioning is a major factor influencing the concentration of several semi-volatile NPAHs and OPAHs in the soils. Complete understanding of the long-term variations of NPAH and OPAH concentrations in soil is limited by the lack of kinetic data describing their formation and degradation.

• Keywords
• Background, Nitrated PAHs, Polycyclic aromatic compounds, soil pollution, Soil exposure, Temporal variation,
• MeSH
• Nitrates MeSH
• Air Pollutants * analysis   MeSH
• Environmental Monitoring methods   MeSH
• Grassland MeSH
• Polycyclic Aromatic Hydrocarbons * analysis   MeSH
• Soil MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Nitrates MeSH
• Air Pollutants * MeSH
• Polycyclic Aromatic Hydrocarbons * MeSH
• Soil MeSH

Secondary plant metabolites (SPMEs) play an important role in plant survival in the environment and serve to establish ecological relationships between plants and other organisms. Communication between plants and microorganisms via SPMEs contained in root exudates or derived from litter decomposition is an example of this phenomenon. In this review, the general aspects of rhizodeposition together with the significance of terpenes and phenolic compounds are discussed in detail. We focus specifically on the effect of SPMEs on microbial community structure and metabolic activity in environments contaminated by polychlorinated biphenyls (PCBs) and polyaromatic hydrocarbons (PAHs). Furthermore, a section is devoted to a complex effect of plants and/or their metabolites contained in litter on bioremediation of contaminated sites. New insights are introduced from a study evaluating the effects of SPMEs derived during decomposition of grapefruit peel, lemon peel, and pears on bacterial communities and their ability to degrade PCBs in a long-term contaminated soil. The presented review supports the "secondary compound hypothesis" and demonstrates the potential of SPMEs for increasing the effectiveness of bioremediation processes.

• Keywords
• bioremediation, carbon flow, community structure, secondary plant metabolites (SPMEs),
• MeSH
• Bacteria classification   isolation & purification   metabolism   MeSH
• Biodegradation, Environmental * MeSH
• Soil Pollutants chemistry   toxicity   MeSH
• Polychlorinated Biphenyls toxicity   MeSH
• Soil Microbiology * MeSH
• Plants metabolism   microbiology   MeSH
• Secondary Metabolism MeSH
• Publication type
• Journal Article MeSH
• Review MeSH
• Names of Substances
• Soil Pollutants MeSH
• Polychlorinated Biphenyls MeSH

White-rot fungi that are efficient lignin degraders responsible for its turnover in nature have appeared twice in the center of biotechnological research - first, when the lignin degradation process started being systematically investigated and major enzyme activities and mechanisms involved were described, and second, when the huge remediation potential of these organisms was established. Originally, Phanerochaete chrysosporium became a model organism, characterized by a secondary metabolism regulatory pattern triggered by nutrient (mostly nitrogen) limitation. Last decade brought evidence of more varied regulatory patterns in white-rot fungi when ligninolytic enzymes were also abundantly synthesized under conditions of nitrogen sufficiency. Gradually, research was focused on other species, among them Irpex lacteus showing a remarkable pollutant toxicity resistance and biodegradation efficiency. Systematic research has built up knowledge of biochemistry and biotechnological applicability of this fungus, stressing the need to critically summarize and estimate these scattered data. The review attempts to evaluate the information on I. lacteus focusing on various enzyme activities and bioremediation of organopollutants in water and soil environments, with the aim of mediating this knowledge to a broader microbiological audience.

• MeSH
• Basidiomycota enzymology   genetics   metabolism   MeSH
• Biodegradation, Environmental MeSH
• Biotechnology * MeSH
• Fungal Proteins genetics   metabolism   MeSH
• Environmental Pollutants metabolism   MeSH
• Lignin metabolism   MeSH
• Gene Expression Regulation, Fungal MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Review MeSH
• Names of Substances
• Fungal Proteins MeSH
• Environmental Pollutants MeSH
• Lignin MeSH

The ligninolytic fungus Irpex lacteus was shown as an efficient degrader of oligocyclic aromatic hydrocarbons (PAHs; 'polycyclic aromatic hydrocarbons') possessing 3-6 aromatic rings in complex liquid media. The strain produced mainly Mn-dependent peroxidase in media without pollutants. Activity of ligninolytic enzymes was higher in a N-limited medium. However, after contamination with PAHs (especially pyrene) the values increased and significant activity of Mn-independent peroxidase appeared in the complex medium. Other factors (such as the increase in nitrogen concentration or the presence of solvent(s) for dissolution of PAHs) had no effect. Cytochrome P-450 was detected in the microsomal fraction of biomass grown in the complex medium. The rate of PAH degradation was also affected by the presence of various combinations of PAHs. However, independently of the enzyme activities, anthracene was shown to have a positive influence on degradation of pyrene and fluoranthene.

• MeSH
• Basidiomycota enzymology   genetics   metabolism   MeSH
• Biodegradation, Environmental MeSH
• Fungal Proteins genetics   metabolism   MeSH
• Lignin metabolism   MeSH
• Peroxidases genetics   metabolism   MeSH
• Polycyclic Aromatic Hydrocarbons chemistry   metabolism   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Fungal Proteins MeSH
• Lignin MeSH
• Peroxidases MeSH
• Polycyclic Aromatic Hydrocarbons MeSH