Transformation of the Recalcitrant Pharmaceutical Compound Carbamazepine by Pleurotus ostreatus: Role of Cytochrome P450 Monooxygenase and Manganese Peroxidase

• Published in: Environmental science & technology 2011-08, Vol.45 (16), p.6800-6805
• Main Authors: Golan-Rozen, Naama, Chefetz, Benny, Ben-Ari, Julius, Geva, Joseph, Hadar, Yitzhak
• Format: Article
• Language: English
• Subjects: Applied sciences; Biodegradation of pollutants; Biodegradation, Environmental - drug effects; Biological and medical sciences; Biological and physicochemical phenomena; Bioremediation; Biotechnology; Biotransformation - drug effects; Carbamazepine - isolation & purification; Carbamazepine - metabolism; Chemical compounds; Culture Media - pharmacology; Cytochrome; Cytochrome P-450 Enzyme System - metabolism; Decontamination. Miscellaneous; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Environment and pollution; Environmental Processes; Enzymes; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; Fungi; Industrial applications and implications. Economical aspects; Natural water pollution; Peroxidases - metabolism; Pharmaceutical Preparations - isolation & purification; Pharmaceutical Preparations - metabolism; Pleurotus - drug effects; Pleurotus - enzymology; Pleurotus - metabolism; Pollution; Pollution, environment geology; Soil and sediments pollution; Water treatment; Water treatment and pollution
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es200298t

Carbamazepine (CBZ) is an environmentally recalcitrant compound highly stable in soil and during wastewater treatment. In this study, we examined the mechanisms by which the white-rot fungus Pleurotus ostreatus metabolizes CBZ in liquid culture using a physiological approach. P. ostreatus PC9 was grown in media known to support different levels of a multiplicity of enzyme systems such as cytochrome P450 (CYP450) and manganese peroxidase (MnP). When both CYP450 and MnP systems were active, 99% of the added CBZ was eliminated from the solution and transformed to 10,11-epoxycarbamazepine. High removal of CBZ was also obtained when either MnP or CYP450 was active. When both CYP450 and MnP were inactivated, only 10 to 30% of the added CBZ was removed. In this latter system, removal of CBZ might be partially attributed to the activity of versatile peroxidase. P. ostreatus was able to eliminate CBZ in liquid culture even when CBZ was added at an environmentally relevant concentration (1 μg L–1). On the basis of our study, we suggest that two families of enzymes are involved in the oxidation of CBZ in liquid culture: MnP in a Mn2+-dependent or independent manner and CYP450. Our study also highlights the potential of using P. ostreatus for bioremediation systems.