Project
Polycyclic aromatic hydrocarbons (PAHs) threaten wildlife as well as humans. They can be found as part of crude
oil. In this way oil spills directly cause PAH pollution in waters. They are toxic to fish and invertebrates and
some of them like naphthalene and phenanthrene accumulate in the food chain. This threatens the ecosystem
following an oil spill. [1] Some PAHs, for example naphthalene, are even thought to be human carcinogenic [2].
Our project aims to reduce the concentration of three PAHs (naphthalene, phenanthrene and pyrene) in riverine biotopes using synthetic biology. In this way we want to mitigate the impact of oil spills and make rivers saver for animals as well as humans.
Our project aims to reduce the concentration of three PAHs (naphthalene, phenanthrene and pyrene) in riverine biotopes using synthetic biology. In this way we want to mitigate the impact of oil spills and make rivers saver for animals as well as humans.
Choosing a safe chassis
Initially we planned to bioremediate oil pollutions using spore forming fungi like for example Pleurotus
ostreatus. Several fungi species produce very reactive exoenzymes able to degrade numerous oil ingredients. Thus
they are very promising chassis for bioremediation [3]. In Addition fungi mycelium was reported to absorb oil,
enhancing degradation abilities even further [4].
However, during our research, problems occurred working with fungi in iGEM. Not only they are more tedious to genetically manipulate, but some of the promising chassis also turned out to be human pathogen. This makes them unable to handle for us, as our lab is on BSL1. In Addition genetically engineering fungi makes biocontainment challenging as fungi spores are stress resistant and could easily escape into the environment [5]. Therefore bioremediation using genetically modified fungi for us seemed unfeasible, as it would be extremely difficult to ensure biocontainment and prevent GMOs spreading into environment uncontrolled.
This is why, in the end, we decided to use the BSL1 bacteria Pseudomonas vancouverensis DSM 8368, which also shows very promising PAH degrading abilities, as chassis.
However, during our research, problems occurred working with fungi in iGEM. Not only they are more tedious to genetically manipulate, but some of the promising chassis also turned out to be human pathogen. This makes them unable to handle for us, as our lab is on BSL1. In Addition genetically engineering fungi makes biocontainment challenging as fungi spores are stress resistant and could easily escape into the environment [5]. Therefore bioremediation using genetically modified fungi for us seemed unfeasible, as it would be extremely difficult to ensure biocontainment and prevent GMOs spreading into environment uncontrolled.
This is why, in the end, we decided to use the BSL1 bacteria Pseudomonas vancouverensis DSM 8368, which also shows very promising PAH degrading abilities, as chassis.
Biocontainment
The effects of a GMO spreading uncontrolled in an ecosystem cannot be predicted and could have severe
consequences. Release of GMOs into the environment would thus be unresponsible.
Nevertheless, we want to use the enormous potential of synthetic biology to degrade dangerous, toxic compounds from oil spills. To achieve this in a safe manner, we decided to immobilize our genetically enhanced bacteria inside a device. Polluted water as well as native riverine life shall pass through it whereas the GMO cannot spread into the biotope. In this way we plan to clean water safely.
In our iGEM project we only got to an in-lab proof of our concept. When thinking about the real-world application of the project, many more thinks would need to be considered. It would be necessary to do intensive testing and research before bringing the device with GMOs outside the lab. It would need to be absolutely ensured that there is no threat of biocontamination, and a permission of local authorities would be needed in most countries. It might also turn out, that immobilization and kill-switch alone are not sufficient and further biocontainment strategies would need to be applied.
Nevertheless, we want to use the enormous potential of synthetic biology to degrade dangerous, toxic compounds from oil spills. To achieve this in a safe manner, we decided to immobilize our genetically enhanced bacteria inside a device. Polluted water as well as native riverine life shall pass through it whereas the GMO cannot spread into the biotope. In this way we plan to clean water safely.
In our iGEM project we only got to an in-lab proof of our concept. When thinking about the real-world application of the project, many more thinks would need to be considered. It would be necessary to do intensive testing and research before bringing the device with GMOs outside the lab. It would need to be absolutely ensured that there is no threat of biocontamination, and a permission of local authorities would be needed in most countries. It might also turn out, that immobilization and kill-switch alone are not sufficient and further biocontainment strategies would need to be applied.
References
[1] M. Honda and N. Suzuki, "Toxicities of Polycyclic Aromatic Hydrocarbons for Aquatic Animals," International journal of environmental research and public health, vol. 17, no. 4, 2020, doi: 10.3390/ijerph17041363.
[2] National Toxicology Program, 15th Report on Carcinogens, 2021. Accessed: Aug. 17 2024. [Online]. Available: https://www.ncbi.nlm.nih.gov/books/NBK590832/
[3] R. Kumar and A. Kaur, "Oil Spill Removal by Mycoremediation," in Microbial Action on Hydrocarbons, V. Kumar, M. Kumar, and R. Prasad, Eds., Singapore: Springer Singapore, 2018, pp. 505–526.
[4] C. Anderson and G. Juday, "Mycoremediation of Petroleum: A Literature Review," JESE, vol. 5, no. 8, 2016, doi: 10.17265/2162-5298/2016.08.002.
[5] Alonso Flores, Working with spore-forming fungi? Remember you need to Check In! [Online]. Available: https://blog.igem.org/blog/2023/5/24/working-with-spore-forming-fungi-remember-you-need-to-check-in (accessed: Aug. 17 2024).
[6] Y. Yang, R. F. Chen, and M. P. Shiaris, "Metabolism of naphthalene, fluorene, and phenanthrene: preliminary characterization of a cloned gene cluster from Pseudomonas putida NCIB 9816," Journal of bacteriology, vol. 176, no. 8, pp. 2158–2164, 1994, doi: 10.1128/jb.176.8.2158-2164.1994.
[2] National Toxicology Program, 15th Report on Carcinogens, 2021. Accessed: Aug. 17 2024. [Online]. Available: https://www.ncbi.nlm.nih.gov/books/NBK590832/
[3] R. Kumar and A. Kaur, "Oil Spill Removal by Mycoremediation," in Microbial Action on Hydrocarbons, V. Kumar, M. Kumar, and R. Prasad, Eds., Singapore: Springer Singapore, 2018, pp. 505–526.
[4] C. Anderson and G. Juday, "Mycoremediation of Petroleum: A Literature Review," JESE, vol. 5, no. 8, 2016, doi: 10.17265/2162-5298/2016.08.002.
[5] Alonso Flores, Working with spore-forming fungi? Remember you need to Check In! [Online]. Available: https://blog.igem.org/blog/2023/5/24/working-with-spore-forming-fungi-remember-you-need-to-check-in (accessed: Aug. 17 2024).
[6] Y. Yang, R. F. Chen, and M. P. Shiaris, "Metabolism of naphthalene, fluorene, and phenanthrene: preliminary characterization of a cloned gene cluster from Pseudomonas putida NCIB 9816," Journal of bacteriology, vol. 176, no. 8, pp. 2158–2164, 1994, doi: 10.1128/jb.176.8.2158-2164.1994.