Cosmopolitan fungi: tools for bioremediation of contaminated soils – MycoRemed

A growing proportion of xenobiotics of anthropogenic origin are contaminants of natural environments, in particular in soils. The use of microorganisms is a promising strategy for bioremediation of contaminated environments. Although bacteria are the most common group of organisms used for bioremediation, filamentous fungi may offer promising alternatives. Indeed, these organisms form the main biomass of the soil microorganisms and fungi out compete bacteria in many metabolic processes, or synergise their activity. We previously showed the potential for bioremediation of the filamentous ascomycete Podospora anserina, a non-pathogenic species, with limited lifespan (Martins et al, 2009). This species expresses an acetylation enzyme (PaNAT2), very active to detoxify aniline derivatives, including 3,4-dichloroaniline (3,4-DCA), a toxic by-product of pesticide found in certain soils. 3,4-DCA belongs to the family of aromatic amines (AA), an important and diversified class of pollutants, including in particular pesticide derivatives, drugs and industrial chemicals.
The overall aim of this research programme is to develop a set of complementary approaches to provide a rational for the use of cosmopolitan fungi as tools for bioremediation of AA-contaminated soils. In order to fulfil the project objectives, the proposed research programme has been divided into three tasks.

1/ The ecotoxicity of AA and of their acetylated products will be assessed in different soils.
2/ Molecular and functional characteristics of their AA detoxification pathways will be studied in several cosmopolitan fungi.
3/ Soils will be contaminated by toxic AA (selected in Task 1), and colonised by fungi (selected in Task 2) to evaluate fungal bioremediation activity.

This research programme requires a multidisciplinary approach (biochemistry, cell and molecular biology, soil ecotoxicology) that will involve the expertise of three complementary research teams (EAC CNRS 4413, UMR CNRS 8621, UR INRA 251). It will provide an experimental basis for designing novel bioremediation systems. One of them, P. anserina, a non-genetically engineered organism devoid of pathogenicity, has already been shown to be promising.