Bioconversion of toxic micropollutant triclosan to 2,4-dichlorophenol using a wastewater isolate Pseudomonas aeruginosa KS2002
- 25 Downloads
Triclosan, a commonly available pesticide, has emerged as a ubiquitous pollutant posing a major threat to the environment. Here we have isolated a wastewater microorganism, Pseudomonas aeruginosa KS2002, capable of converting triclosan to 2,4-dichlorophenol within 96 h of incubation. The confirmation of the end product was done using Fourier transform infrared spectroscopy and mass spectroscopy. Different minimal media were investigated to establish a suitable media supporting maximum triclosan degradation. Spectral analysis showed that this bacterial isolate degraded 99.89% ± 0.3 of 2 g/L of triclosan spiked in an M9 minimal salt medium. This isolate utilized fructose and glycerol as a co-substrate to enhance degradation process. The cell-free extract of Pseudomonas aeruginosa KS2002 showed the activity of catechol 2,3-dioxygenase enzyme (specific enzyme activity = 0.161 U/mg). In the presence of 3-fluorocatechol, a meta-cleavage enzyme inhibitor, triclosan degradation was ceased suggesting a meta-cleavage pathway for triclosan degradation. Keeping in view the observations recorded, we proposed a pathway for partial triclosan degradation using this isolate.
KeywordsCatechol 2,3-dioxygenase 3-fluorocatechol Mass spectroscopy Meta-cleavage
The authors are extremely thankful to the Council of Scientific and Industrial Research (Scheme No. 24(0340)/16/EMR-II) for providing financial assistance for the research work. We would also like to acknowledge Department of Bio-Engineering and Central Instrumentation Facility (CIF) at Birla Institute of Technology, Mesra, for providing us with the infrastructure to conduct our research work.
Compliance with ethical standards
Conflict of Interests
The authors declare that they have no conflict of interest.
- Holt JG, Kreig NR, Sneath PHA, Staley JT, Williams ST (1994) Bergey’s manual of determinative bacteriology, 9th edn. Williams and Wilkins, BaltimoreGoogle Scholar
- Hovander L, Malmberg T, Athanasiadou M, Athanassiadis I, Rahm S, Bergman A, Wehler EK (2002) Identification of hydroxylated PCB metabolites and other phenolic halogenated pollutants in human blood plasma. Arch Environ Contam Toxicol 42:105–117. https://doi.org/10.1007/s002440010298 CrossRefGoogle Scholar
- Lakshmi MVVC, Sridevi V, Neharika E, Beena CH, Rao MN, Swamy AVN (2009) Effect of temperature and carbon source on phenol degradation by Pseudomonas aeruginosa (NCIM 2074) and Pseudomonas desmolyticum (NCIM 2028) and their comparison. Int J Chem Sci 7:2591–2601Google Scholar
- Mathew J, Joy NS, Kuppuswamy S (2017) A review on “Triclosan a controversial antibacterial”. Int J Pharm Pharm Res 8:200–216Google Scholar
- Meade MJ, Waddell RL, Callahan TM (2001) Soil bacteria Pseudomonas putida and Alcaligenes xylosoxidans subsp. denitrificans inactivate triclosan in liquid and solid substrates. FEMS Microbiol Lett 204:45–48. https://doi.org/10.1111/j.1574-6968.2001.tb10860.x CrossRefGoogle Scholar
- Schweizer HP (2001) Triclosan: a widely used biocide and its link to antibiotics. FEMS Microbiol Lett 202:1–7. https://doi.org/10.1111/j.1574-6968.2001.tb10772.x CrossRefGoogle Scholar
- Toyama T, Momotani N, Ogata Y, Miyamori Y, Inoue D, Sei K, Mori K, Kikuchi S, Ike M (2010) Isolation and characterization of 4-tert-butylphenol-utilizing Sphingobium fuliginis strains from Phragmites australis rhizosphere sediment. Appl Environ Microbiol 76:6733–6740. https://doi.org/10.1128/AEM.00258-10 CrossRefGoogle Scholar
- Zhao F (2006) Biodegradation of triclosan by a triclosan-degrading isolate and an ammonia oxidizing bacterium. Dissertation, Texas A&M University. http://hdl.handle.net/1969.1/5966