How do you envision others using your project? What are the security issues you should consider?
We visualized a simple but practical device considering that it will be necessary to take into account the technical capabilities for the correct use of the device, for this reason the creation of the device was intuitive and clear recommendations were made on the proper use of our biosensor. When applied in rural and urban communities where there is the possibility of not correctly understanding its use and the negative consequences that could result. If the instructions are followed correctly there will be no problems. Our biosafety protocol is clear and specific , and details the aspects of how it should be disposed of, not consuming the product, the device and taking care that it does not come into contact with water or sewage drainage. It is recommended that it be incinerated after use, since in rural communities there are no optimal conditions for conventional disposal of biological waste (1).
In case of an oversight that could allow the release of the biosensor into the environment, we are thinking of options to avoid unintended release of GMOs into the environment. To this end, we reviewed biocontainment methods. These have high costs and technical aspects that are beyond our context and economic capacity. It is something that has been studied, but has not been applied. We investigated that biocontainment systems that combine environmental sensing with circuit-based cell viability monitoring could be used to prevent leakage of genetically modified microbes into the environment. Toxin and antitoxin kill switches. The kill switch uses unbalanced reciprocal transcriptional repression to couple a specific input signal with cell survival. These synthetic genetic circuits effectively kill Escherichia coli and can be easily reprogrammed to change their environmental inputs, regulatory architecture and death mechanism (1).
Antitoxin toxin system (1)
closeOur proposed end-users & how we envision them using our project
As the Bolivia team, we identified that the community members in urban and rural areas will benefit from the visibility of their problems. However, when reflecting on the whole social and educational context we came to the conclusion that the best end users to make use of the Biosensor should be:
Researchers
Initially we considered rural and urban communities as our direct end users. However, we realized that in Bolivia several researchers are making a concerted effort to identify the problems caused by the presence of arsenic in water for the people affected in terms of public health (2). These researchers need to resort to highly specialized detection methods that are difficult to access in rural areas where conditions are not the best to house such equipment, which makes the water sampling process exponentially more difficult. In addition, correctly confirming the data obtained requires a large investment of physical energy and resources due to the long distances that must be traveled to sample wells, bodies of water and send them to the laboratory. With Arsemaphore we accelerate the above mentioned processes.
Companies
Likewise, we consider as end users those institutions specialized in water remediation of As and other heavy metals such as AGUATUYA and CASA, who showed great interest in the biosensor as a tool to facilitate the detection of arsenic in contaminated water. For example, Mr. Renato Montoya, Executive Director of the AGUATUYA, allowed us to visit some of the wastewater treatment plants, which are developed in the municipality of Sacaba (3). The plant has a purification tool to remove organic matter that pollutes the water. When he heard about our project, he felt very interested because the presence of heavy metals in contact with bacteria affects their viability. For this reason our biosensor would help to prevent the inefficiency of the plant. At the same time, we were offered to test our biosensor along the validation with the plant, for about 6 months. This event will allow us to improve our biosensor under different scenarios.
closeHow we would implement our project in the real world: Arsemaphore in the real world
From the activities carried out with experts in the social area and our research, we thought that the use of synthetic biology would generate susceptibility and possible reluctance to accept our project as a solution. However, with the visits we made to the communities we realized that we were wrong. The success obtained in our visits and interaction with community members was due to the methodology we used to integrate our project. For this reason, the implementation of the biosensor will include educational actions to sensitize the population to understand the solutions from synthetic biology and guarantee the necessary biosafety measures
A device that helps end users
Considering aspects such as health, bacteria should not come into direct contact with the person, because it is handled by means of a device; which will determine the samples under study. Through the mechatronic device it is possible to interpret, record and disseminate the manifestations of bacteria from 18 different samples quickly and accurately in a small space, being its main objective to accompany and enhance the biosensor, considering as an important feature to reduce the exposure time of the operator with the bacteria. The information obtained may be observed by the operator in real time in addition to being transmitted via Wireless (wireless signals). It is portable and has an independent battery to facilitate its use by technicians. The device will report semi-quantitative results compared to atomic absorption spectrophotometry(5) which provides quantitative ones. However , our device facilitates expeditions to regions of our country where it is not easy to access the use of mass spectrophotometry. Our response time is a maximum of 24 hours. This helps a lot in mass data collection, it is field accessible, mobile, it is much cheaper.
closeSPECIAL AWARDS
BEST INTEGRATE HUMAN PRACTICE
Conclusion about “The Problem & Our Human-Centered Approach”
In the year 2021, it became clear to the world that it was urgent and our responsibility to take climate change issues seriously. Therefore, to contribute to the recovery of the water bodies, we have developed a Biosensor for Arsenic detection which is affordable, and will allow us to democratize the use of synthetic biology in Bolivia. It is our understanding that this will not solve the problem, consequently, it remains vitally important to generate tools that comprises all the necessary steps from collection, treatment, and distribution of water.
The proposal of the Bolivian team is the development of a Biosensor for the detection of Arsenic in drinking water, it is a whole cell Biosensor in which an E. coli DH5α will be transformed with a genetic circuit designed by the Bolivian team. It will have specificity for arsenic, and it will contain a detection module, processing module, and output module, resulting in a signal that is characterized by the color change of chromoproteins. It is measurable in case of the presence of arsenic in the studied water samples.
Other challenges to be considered: To future and solutions
We are aware that our project does not solve the As problem in the urban and rural communities that we visited. However, our commitment and responsibility towards the communities that allowed us to make their problems visible, it is up to us to explore solutions so that in the future the Bolivia team can be part of the solutions to the presence and contamination of As.
Mechanisms of Arsenic Transformation by Bacteria
In our research on bioremediation, we found that bacteria are versatile due to all different metabolic pathways they present. Arsenic resistant microorganisms are capable of detoxifying their cells by the transport of arsenic, either in its oxidized form of arsenate or in the reduced form of arsenite. Microorganisms that live in arsenic rich environments, and transform As(V) to As(III) are present in different branches of the tree of life, but they should have three main enzyme systems:
- Arsenite oxidase
- Arsenate reductase
- Cytoplasmic arsenate reductase, cytoplasmic arsenate reductase and cytoplasmic arsenate reductase.
A large number of Gram-negative and Gram-positive bacteria employ a common arsenic resistance mechanism based on the arsRDABC operon encoding five genes, which corresponds to the most studied arsenic detoxification system and is involved in the reduction of arsenate to arsenite by the enzyme arsenate reductase that expels arsenite out of the cell using an arsenic ejector pump(6).
References:
- Clement TY Chan, Jeong Wook Lee, D. Ewen Cameron , Caleb J. Bashor and James J. Collins (2016). 'Deadman' and 'Passcode' microbial kill switches for bacterial containment. Nat Chem Biol 12, 82–86
- De Loma J., Gliga, A., Levi, M., Ascui, F., Gardon, J., Tirado, N. y Broberg, K. (2020). Exposición al arsénico y proteínas relacionadas con el cáncer en la orina de mujeres indígenas bolivianas. Frontiers. Salud Pública, 8(605123). Read more
- Aguatuya. (2016). Se inaugura la planta de tratamiento de aguas residuales de Curubamba, en Sacaba. Read more
- Funes, F., Panozo, A. y Cardozo, T. (2005). Manual de Bioseguridad Y Bioprotección: En Ámbitos Universitarios Y Hospitalarios (1era ed.). Impresiones Poligraf. Read more
- Martinez, L y Gasquez, J. (2005, del 25 al 28 de octubre).Determinación de arsénico en aguas: diferentes técnicas y metodologías [seminario;congreso]. IIº Seminario Hispano-Latinoamericano sobre temas actuales de hidrología subterránea; IVº Congreso Hidrogeológico Argentino, San Luis, Argentina.
- Rodríguez, L., Peña, M., Gutiérrez, A., González, C., Montes, S. y López, G. (2017). Biorremediación de arsénico mediada por microorganismos genéticamente modificados. Tierra latinoamericana, 35(4), 353–361.
- Escalera, R., Ormachea, M., Ormachea, O. y Heredia, M. (2014). Presencia natural de arsénico en aguas de pozos profundos y su remoción usando un prototipo piloto basado en colectores solares de bajo costo. Investigación & desarrollo, 2(14), 85 – 93.
- Saavedra, J. (2021, 13 de junio). El proyecto de ley de OGM y una moratoria. Diario Página Siete. Read more