title: Biotransformation of β-hexachlorocyclohexane by the saprotrophic soil fungus Penicillium griseofulvum.
abstract: β-Hexachlorocyclohexane (β-HCH) is a persistent organic pollutant (POP) of global concern with potentially toxic effects on humans and ecosystems. Fungal tolerance and biotransformation of toxic substances hold considerable promise in environmental remediation technologies as many fungi can tolerate extreme environmental conditions and possess efficient extracellular degradative enzymes with relatively non-specific activities. In this research, we have investigated the potential of a saprotrophic soil fungus, Penicillium griseofulvum Dierckx, isolated from soils with high concentrations of isomers of hexachlorocyclohexane, to biotransform β-HCH, the most recalcitrant isomer to microbial activity. The growth kinetics of the fungus were characterized after growth in stirred liquid Czapek-Dox medium. It was found that P. griseofulvum was able to grow in the presence of 1 mg L(-1) β-HCH and in stressful nutritional conditions at different concentrations of sucrose in the medium (0 and 5 g L(-1)). The effects of β-HCH and the toluene, used as a solvent for β-HCH addition, on P. griseofulvum were investigated by means of a Phenotype MicroArray™ technique, which suggested the activation of certain metabolic pathways as a response to oxidative stress due to the presence of the xenobiotics. Gas chromatographic analysis of β-HCH concentration confirmed biodegradation of the isomer with a minimum value of β-HCH residual concentration of 18.6%. The formation of benzoic acid derivatives as dead-end products of β-HCH biotransformation was observed and this could arise from a possible biodegradation pathway for β-HCH with important connections to fungal secondary metabolism.
authors.affiliation: Laboratorio Biodiversità dei Funghi, Dipartimento di Biologia Ambientale, Sapienza Università di Roma, Rome 00185, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Ceci
authors.affiliation: Laboratorio di impianti e processi industriali, Dipartimento di Chimica, Sapienza Università di Roma, Rome 00185, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Pierro
authors.affiliation: Settore Ricerca, Certificazione e Verifica, INAIL, Monteporzio Catone, Rome 00040, Italy.
authors.forename: Carmela
authors.initials: C
authors.lastname: Riccardi
authors.affiliation: Consiglio per la Ricerca e l'Analisi dell'Economia Agraria, Centro di ricerca per lo studio delle Relazioni tra Pianta e Suolo, Rome 00184, Italy.
authors.forename: Flavia
authors.initials: F
authors.lastname: Pinzari
authors.affiliation: Laboratorio Biodiversità dei Funghi, Dipartimento di Biologia Ambientale, Sapienza Università di Roma, Rome 00185, Italy.
authors.forename: Oriana
authors.initials: O
authors.lastname: Maggi
authors.affiliation: Laboratorio Biodiversità dei Funghi, Dipartimento di Biologia Ambientale, Sapienza Università di Roma, Rome 00185, Italy.
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Persiani
authors.affiliation: Geomicrobiology Group, College of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, UK; Laboratory of Environmental Pollution and Bioremediation, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, People's Republic of China.
authors.forename: Geoffrey Michael
authors.initials: GM
authors.lastname: Gadd
authors.affiliation: Laboratorio di impianti e processi industriali, Dipartimento di Chimica, Sapienza Università di Roma, Rome 00185, Italy. Electronic address: marco.petrangelipapini@uniroma1.it.
authors.forename: Marco
authors.initials: M
authors.lastname: Petrangeli Papini
mesh_terms: D001565:Benzoates / Q000032:analysis; D001673:Biodegradation, Environmental; D001711:Biotransformation; D017753:Ecosystem; D001556:Hexachlorocyclohexane / Q000032:analysis* / Q000378:metabolism; D007536:Isomerism; D053858:Metabolic Networks and Pathways; D055442:Metabolome; D010407:Penicillium / Q000378:metabolism*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis* / Q000378:metabolism
chemical_list: D001565:Benzoates; D012989:Soil Pollutants; D001556:Hexachlorocyclohexane; C023888:beta-hexachlorocyclohexane
keywords: Biodegradation; Biotransformation; Penicillium griseofulvum; Phenotype microarray; Soil fungi; β-Hexachlorocyclohexane (β-HCH)