How genetically modified organisms could transform water treatment

18 December 2024

Tailored microbes can efficiently remove pollutants like microplastics, hydrocarbons, metals and oils from water – so what’s stopping the water sector from embracing their potential?

Synthetic biology tools for producing water-cleaning microbes have been available for years. Tailored microbes with enhanced capabilities, designed through precise manipulation, can efficiently remove pollutants like microplastics, hydrocarbons, metals and oils.

They have huge potential for the water industry globally, through significantly reducing the need for chemical dosing, opening new revenue streams through the recovery of valuable resources such as phosphorus and ammonia, and offering the potential for rapid biosensing, providing early warning systems for water quality issues.

Challenges to adoption

Despite these benefits, synthetic biology tools have largely stayed in the lab. Their widespread adoption in water treatment has been hindered by several challenges, the most critical of which being the need to ensure the stability and resilience of ecosystems when introducing engineered microbes. It’s essential to guarantee that these engineered organisms do not disrupt the natural dynamics of microbial communities.

Public acceptance is also crucial, particularly given the historical concerns around GMOs in agriculture. Transparency, controlled testing, gradual scaling from lab experiments to real-world applications, and clear regulatory frameworks will all be necessary steps to address these concerns.

Another challenge is maintaining the performance of these microbes through the cycles of changing environments. For microbes to remain effective, their key properties must be maintained, which often require them to be kept under stress. However, as their environment changes — or the microbes develop resistance — their performance is reduced; the water industry needs to find ways to improve consistency and stability.

Making microbes

In the UK, significant progress is being made. The Environmental Biotechnology Innovation Centre (EBIC) is at the forefront of this effort, establishing the necessary testing and biosecurity frameworks to enable the deployment of pollution-targeting microbes within the national water and wastewater systems. Led by Cranfield University, this five-year project, established in early 2024, is funded by the UKRI BBSRC Engineering Biology Programme, and involves a network of leading UK universities, each member of which works on different elements of the process of editing, management and the practical application of microbes.

Recent years have seen important developments in the potential of synthetic biology. These include the use of more accurate genome editing technologies, such as CRISPR-Cas9, which allow for the design of micro-organisms with very specific characteristics and capabilities, including how organisms work together as a social, multicellular collective. There are three essential approaches to editing: a microbe can be added to improve a particular type of performance; a ‘minimalist cell’ can be created by removing microbes, causing a cell to become more focused on a specific role; or cells can be used solely as carriers which simply release enzymes.

In the water sector, that means a tailored mechanism for improving the performance of treatment and the capture of materials with a commercial value — as well as providing a biosensor system for early warnings on pollution. The potential of synthetic biology extends far beyond water treatment, with applications in healthcare (such as the rapid detection of pathogens); security (surveillance and detection of illegal drugs at borders); and recovery of valuable resources from waste sites. Biotechnological applications include industries making use of surfactants in the manufacture of products like detergents, paints and motor oils.

Significant progress has already been made at lab scale, with the development of advanced mathematical models to better understand how synthetic and natural microbes interact as collectives. These models are used to help improve and speed up the typical cycle of design, build, test and learn, so fewer cycles are needed.

Biosecurity guaranteed

The next step, through EBIC, is to establish a ‘closed loop’ system for testing at a larger scale in a real-world environment, all while ensuring full biosecurity by preventing any release of genetically modified microbes into broader ecosystems. This approach will be underpinned by rigorous organisation, mapping and standards. In this way, the UK will be able to follow the US example around synthetic biology, where work is progressing under the management of the Engineering Biology Research Consortium (EBRC), a non-profit, public-private partnership.

The EBRC has put together working groups to co-ordinate research roadmapping, education, security, and policy and international engagement. Plans for a similar approach in the UK are being discussed alongside the Biotechnology and Biological Sciences Research Council (BBSRC), reflecting the importance of engineering biology as one of the government’s five critical technologies in its Science and Technology Framework.

Critically, EBIC is also working with the National Physical Laboratory (NPL) and the UK National Measurement Laboratory (NML) to establish standards for the bio-tools involved. This will create the basis for transparent controls and records, with each newly-edited microbe being given a barcode and entered into a library of engineered microbes. In this way, we have a means of tracking provenance – who produced which microbes, where and when — ensuring complete traceability and responsibility.

This kind of responsible, safe scaling up of techniques from synthetic biology, biotechnology, computation modelling and engineering science will provide a platform for transformational solutions. It positions the water industry at the forefront of a new era of clean, sustainable technologies.

Author: Professor Frederic Coulon is director of the Environmental Biotechnology Innovation Centre at Cranfield University.