Biotransformation of benzo[a]pyrene by the thermophilic bacterium Bacillus licheniformis M2-7
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Benzo[a]pyrene (BaP) is recognized as a potentially carcinogenic and mutagenic hydrocarbon, and thus, its removal from the environment is a priority. The use of thermophilic bacteria capable of biodegrading or biotransforming this compound to less toxic forms has been explored in recent decades, since it provides advantages compared to mesophilic organisms. This study assessed the biotransformation of BaP by the thermophilic bacterium Bacillus licheniformis M2-7. Our analysis of the biotransformation process mediated by strain M2-7 on BaP shows that it begins during the first 3 h of culture. The gas chromatogram of the compound produced shows a peak with a retention time of 17.38 min, and the mass spectra shows an approximate molecular ion of m/z 167, which coincides with the molecular weight of the chemical formula C6H4(COOH)2, confirming a chemical structure corresponding to phthalic acid. Catechol 2,3-dioxygenase (C23O) enzyme activity was detected in minimal saline medium supplemented with BaP (0.33 U mg−1 of protein). This finding suggests that B. licheniformis M2-7 uses the meta pathway for biodegrading BaP using the enzyme C23O, thereby generating phthalic acid as an intermediate.
KeywordsBenzo[a]pyrene Phthalic acid Bacillus licheniformis Biotransformation Thermophilic bacteria Catechol 2,3-dioxygenase
This work was supported by Grants 249671 from Consejo Nacional de Ciencia y Tecnología and by Agreement 2014 of the University of Guerrero. Joseph Guevara-Luna thanks Consejo Nacional de Ciencia y Tecnología for MSc Scholarship (402669). We are grateful to Travis Ashworth for the critical discussions of this work.
- Annweiler E, Richnow HH, Antranikian G, Hebenbrock S, Garms C, Franke S, Francke W, Michaelis W (2000) Naphthalene degradation and incorporation of naphthalene-derived carbon into biomass by the thermophile Bacillus thermoleovorans. Appl Environ Microbiol 66(2):518–523. https://doi.org/10.1128/AEM.66.2.518-523.2000 CrossRefPubMedPubMedCentralGoogle Scholar
- Đokić L, Narancic T, Nikodinovic-Runic J, Bajkic S, Vasiljevic B (2011) Four Bacillus sp. soil isolates capable of degrading phenol, toluene, biphenyl, naphthalene, and other aromatic compounds exhibit different aromatic catabolic potentials. Arch Biol Sci 63(4):1057–1067. https://doi.org/10.2298/ABS1104057D CrossRefGoogle Scholar
- Guzik U, Hupert-Kocurek K, Sitnik M, Wojcieszyńska D (2013) High activity catechol 1,2-dioxygenase from Stenotrophomonas maltophilia strain KB2 as a useful tool in cis, cis-muconic acid production. Antonie Van Leeuwenhoek 103(6):297–1307. https://doi.org/10.1007/s10482-013-9910-8 CrossRefGoogle Scholar
- IARC Working Group on the Evaluation of Carcinogenic Risks to Humans (2010) Some non-heterocyclic polycyclic aromatic hydrocarbons and some related exposures. IARC monographs on the evaluation of carcinogenic risks to humans, no. 92. International Agency for Research on Cancer, Lyon. https://www.ncbi.nlm.nih.gov/books/NBK321712/
- Mohamed ME, Al-Dousary M, Hamzah RY, Fuchs G (2006) Isolation and characterization of indigenous thermophilic bacteria active in natural attenuation of bio-hazardous petrochemical pollutants. Int Biodeterior Biodegradation 58(3–4):213–223. https://doi.org/10.1016/j.ibiod.2006.06.022 CrossRefGoogle Scholar
- Ping L, Zhang C, Zhang C, Zhu Y, He H, Wu M, Tang T, Li Z, Zhao H (2014) Isolation and characterization of pyrene and benzo[a]pyrene-degrading Klebsiella pneumonia PL1 and its potential use in bioremediation. Appl Microbiol Biotechnol 98(8):3819–3828. https://doi.org/10.1007/s00253-013-5469-6 CrossRefPubMedGoogle Scholar
- Rey MW, Ramaiya P, Nelson BA, Brody-Karpin SD, Zaretsky EJ, Tang M. Lopez de Leon A, Xiang H, Gusti V, Clausen IG, Olsen PB, Rasmussen MD, Andersen JT, Jørgensen PL, Larsen TS, Sorokin A, Bolotin A, Lapidus A, Galleron N, Ehrlich SD, Berka RM (2004) Complete genome sequence of the industrial bacterium Bacillus licheniformis and comparisons with closely related Bacillus species. Genome Biol 5(10):R77. https://doi.org/10.1186/gb-2004-5-10-r77 CrossRefPubMedPubMedCentralGoogle Scholar
- US EPA (1984). List of the sixteen PAHs with highest carcinogenic effect. IEA Coal Research, London. https://books.google.com.mx/books
- Zhang J, Zhang X, Liu J, Li R, Shen B (2012) Isolation of a thermophilic bacterium. Geobacillus sp. SH-1, capable of degrading aliphatic hydrocarbons and naphthalene simultaneously, and identification of its naphthalene degrading pathway. Bioresour Technol 124:83–89. https://doi.org/10.1016/j.biortech.2012.08.044 CrossRefPubMedGoogle Scholar