Enhancing microbial energy production

For more than a century, burning fossil fuels has generated most of the energy required to propel our cars, power our businesses and keep the lights on in our homes. Even today, oil, coal and gas provide for about 80% of our energy needs.

Unsustainable energy usage has exacted an enormous toll on humanity and the environment - from air and water pollution to global warming, and in order to stop it, scientists, along with all the other inhabitants of our planet have to work together on solving these issues in order to efficiently minimise their impact.

Who are we?


We are a multicultural team of biology and computer science students from the University of Westminster who were given the opportunity to take part in one of the biggest science competitions on the planet - the international Genetically Engineered Machine (iGEM) - and represent our University with a unique engineering project using the foundations of modern sciences in molecular biology and genetics, with the aim of solving real world problems.

By becoming a part of the iGEM community, we have been given access to a library of genetic components, called BioBricks, that can be used to perform specific functions that an engineer might want to use for designing a product, simply put. The current extent of this library is the product of over 15 years of work done by over a thousand of high school, undergraduate and postgraduate university teams, offering us various well characterised BioBricks that we can use as a foundation for our project, allowing us to focus more on the complicated specifics of our own work.

With months of academic, bioinformatic and laboratory research in the Cavendish campus of our university, we are hoping to bring new insights in the search for new sustainable forms of energy, while addressing some of the most important problems of modern sustainability.

The main focus of our study is the bacteria called Shewanella oneidensis. It is a type of facultative anaerobic bacteria with a peculiar ability of using ions outside the cell as final electron acceptors (termed as 'exo-electrogenic ability') (Kouzma et al, 2015). In other words, this bacteria ‘breathes’ by using metals in a similar way that we breathe by using oxygen. This property attracted scientists to use it for harvesting its electrons through electrochemical devices called Microbial Fuel Cells (See figure 1).

Figure 1: A simplified demonstration of a Microbial Fuel Cell's inner functioning (Rabaey and Verstraete, 2005). It works much like a galvanic cell, with the microbe playing its role in the anode and electrons traveling towards the cathode, resulting with an electric current generating energy.

Figure 2: Our microbial fuel cells.

With the help of Dr. Godfrey Kyazze's laboratory, our goal is to modify these bacteria and improve on the design of MFCs to explore the ways in which their efficiency could be improved. As geneticists, our focus are protein components of the large MtrCAB transmembrane complex, as a part of the Mtr respiratory pathway found in Shewanella oneidensis which appears to be responsible for the final steps of electron transduction.

Figure 1: The proposed mechanism for the mtr pathway, with separate components highlighted.

The Mtr pathway is not very well understood, but from what research suggests, its activity is fully dependent on the presence of a few key identified components, one of which is the MtrCAB complex (check figure 1 for a proposed mode of action) (Shi et al, 2006). We found that specific amino acid chains inside of two proteins, MtrC and OmcA, might be responsible for carrying electrons from the protein directly onto metal surfaces and we believe that we found a way to modify these chain sequences to equip a better electron preservation ability and can then be turned into our own BioBricks. We are testing out all our BioBricks using MFCs.



Our second goal is to test different ways of improving the Shewanella's activity by focusing on other aspects of its metabolism. We will be testing relatively new research on biosurfactants and expression factors that were found to be involved in stimulating the bacteria to reduce metals, by which we could indirectly increase exoelectrogenic ability of these bacterial strains (Zheng et al, 2015).

While we believe that the future of sustainable energy might lie in microbial abilities in biology, one application of MFCs we are also excited about is an idea of coupling the reactions of plastic breakdown together with microbial production of electrical currents in microbial fuel cells. This idea involves a top-to-bottom generation of a model system, which concerns components all the way from the overall design of the bioreactor / MFC inside of which our co-cultures would grow, down to the molecular level observing the enzymatic mechanisms and pathways by which this conversion would occur.


Due to the scale of this idea, we have set up collaborations with other iGEM teams, such as TU Kaiserlautern from Germany, which is working on degradation of PET plastics using microalgae, as well as Ionis from Paris, which are working on the degradation of cellulose acetate, a plastic found in cigarette buds, using bacteria. These teams will help us gather valuable data that can gradually help with adjusting our mathematical model and making the final product of this research applicable in the real world.

Figure x: Collaboration experiments!

If correctly and successfuly characterised, our data could offer valuable research materials for future iGEM teams, academic laboratories and possibly even for real world applications in tackling these issues.
So far, we managed to build a fully functional MFC, test out the transforming ability of our bacterial cells and design the experiments that we need to characterise our BioBricks.

Aside from the laboratory aspect of our work, we are also aiming to raise awareness of the issues we are working against, as well as promoting the use of synthetic biology and genetic engineering as a powerful tool and technology against various issues. Some of the activities we have done so far include participating in a middle school science fair, collaborating with our University’s sustainability team, obtaining energy usage data from the University campuses and accommodation centers, obtaining sustainability data through surveys along with many others and more to come; such as visiting schools and teaching the children about our causes and biology, participating in UK and European iGEM meet-ups, synthetic biology conferences and various other small collaborations with other iGEM teams.

One thing preventing us from realising our goals and performing our experiments is money.

Many iGEM teams are fully funded by their Universities to work on their projects as on full time summer jobs. For us, this is not the case, and many of our members need to do part time jobs to survive while working on the project. This is strongly limiting our working capacity and posing an issue for presenting our results at the official iGEM conference in Boston, USA by the end of October, for which we also need to fund our own flights, accommodation and personal expenses while staying there.

So far, we managed to get sponsored by 5 biotech companies that are offering us a variety of laboratory materials and software we can use to design our experiments.

If we manage to raise £10,000, we will be able to gather all the rest of necessary laboratory materials we need to independently work on our experiments, as well as afford for all the members to travel to Boston, accommodate and cover all their expenses trouble-free.

Any additional funds we manage to raise will be directly distributed to all the members who cannot afford the time to work on the project due to money-related issues, which will directly increase our working output and help with validating our results.

If you are willing to donate money through a company, contact us directly on our email and we will showcase you as our sponsor on our website, project poster, merchandise and conference presentation.

If you want to find out more about the project and see the final results of our work, you can access our website from this link:

2019.igem.org/Team:Westminster_UK

And if you want to follow us as we progress with our work, our instagram account is @igem.uow and twitter account is @WestminsteriGEM.


Sincerely from the team,

If you read this through, thank you for your consideration, and if you donated, thank you for your help!




References:

Kouzma, A., Kasai, T., Hirose, A., Watanabe, K. (2015). Catabolic and regulatory systems in Shewanella oneidensis MR-1 involved in electricity generation in microbial fuel cells. Frontiers in Microbiology.

Rabaey, K. and Verstraete, W. (2005). Microbial fuel cells: novel biotechnology for energy generation. Trends in Biotechnology, 23 (6).

Shi, L. Et al (2006). Isolation of a high-affinity functional protein complex between OmcA and MtrC: Two outer membrane decaheme c-type cytochromes of Shewanella oneidensis MR-1. Journal of Bacteriology.

Zheng, T., Xu, Y. S., Yong, X. Y., Li, B., Yin, D., Cheng, Q. W., Yuan, H. R., Yong, Y. C. (2015). Endogenously enhanced biosurfactant production promotes electricity generation from microbial fuel cells. Bioresour Technol, 197, 416-21.