Understanding fungal functional biodiversity during the mitigation of environmentally dispersed pentachlorophenol in cork oak forest soils

Abstract

Pentachlorophenol is globally dispersed and contamination of soil with this biocide adversely affects its functional biodiversity, particularly of fungi -key colonisers. Their functional role as a community is poorly understood, although a few pathways have been already elucidated in pure cultures. This constitutes here our main challenge -elucidate how fungi influence the pollutant mitigation processes in forest soils.Circumstantial evidence exists that cork oak forests in N.W. Tunisia -economically critical managed forests, are likely to be contaminated with pentachlorophenol but the scientific evidence has previously been lacking. Our data illustrate significant forest contamination through the detection of undefined active sources of pentachlorophenol. By solving the taxonomic diversity and the pentachlorophenol-derived metabolomes of both the cultivable fungi and the fungal community we demonstrate here that most strains (predominantly penicillia) participate in the pollutant biotic degradation. They form a array of degradation intermediates and by-products, including several hydroquinone, resorcinol and catechol derivatives, either chlorinated or not.The degradation pathway of the fungal community includes uncharacterised derivatives, e.g. tetrachloroguaiacol isomers. Our study highlights fungi key role in the mineralisation and short lifetime of pentachlorophenol in forest soils and provide novel tools to monitor its degradation in other fungi dominated food-webs.

Specialisation events of fungal metacommunities exposed to a persistent organic pollutant are suggestive of augmented pathogenic potential

“…Recently, we showed the existence of undefined active sources of PCP pollution in the Tabarka district (Tunisia), particularly in soils collected within cork oak forests [ 4 , 7 ]. The soils were contaminated with PCP levels ranging from 13 to 28 μg/kg of soil.…”

“…The soils were contaminated with PCP levels ranging from 13 to 28 μg/kg of soil. The source and history of the pollution in these soils is unknown [ 4 , 7 ]. Furthermore, we demonstrated that fungi isolated from these PCP-polluted forest soils can extensively degrade PCP, in theory acting as a buffer against PCP pollution in these habitats [ 7 ].…”

“…The source and history of the pollution in these soils is unknown [ 4 , 7 ]. Furthermore, we demonstrated that fungi isolated from these PCP-polluted forest soils can extensively degrade PCP, in theory acting as a buffer against PCP pollution in these habitats [ 7 ]. Due to their remarkable catabolic capacities, ubiquitous occurrence and lifestyle [ 8 ], saprotrophic fungi possess a peerless ability to degrade harmful chemicals, such as PCP [ 7 , 9 – 11 ].…”

“…Furthermore, we demonstrated that fungi isolated from these PCP-polluted forest soils can extensively degrade PCP, in theory acting as a buffer against PCP pollution in these habitats [ 7 ]. Due to their remarkable catabolic capacities, ubiquitous occurrence and lifestyle [ 8 ], saprotrophic fungi possess a peerless ability to degrade harmful chemicals, such as PCP [ 7 , 9 – 11 ]. However, regardless of their ability to mitigate pollutants in soils, these activities raise several concerns: How are their communities affected by pollutants at the taxonomic and functional levels?…”

Ionic Liquids as Unforeseen Assets to Fight Life-Threatening Mycotic Diseases

“…Our front-runner candidates for study organisms were undoubtedly filamentous fungi. Fungi, which are unique and remarkable eukaryotic organisms, act as key colonizers of the soil and ensure major ecosystem functions, including the mitigation of hazardous chemicals ( Harms et al, 2011 ; Varela et al, 2015 ). Moreover, these organisms are well known as proficient producers of enzymes and metabolites of great biotechnological and pharmacological interest.…”