Team:Aachen/HP/Gold Integrated

iGEM Team Aachen 2017

Developing an Idea

With the help of industry and research, we developed our idea to meet both scientific and societal standards. Starting with a system focused on NaCl-Uptake and a vague application in water treatment we concluded in creating the vision of microbial supercollectors for all kinds of substances, proving this vision by storing potassium in a novel yeast. Additionally, we found clear answers on biosafety and fields of application, using well-established membrane technology to remove yeast from water in an energy-efficient way.

Read the following flowchart to gather an overview of our project development and how we were influenced during our journey. By clicking the figures and pictures you get detailed information on the different cooperations.

Werra Salinization

Initial Idea

The Werra is polluted with high concentrations of NaCl due to wastewaters from potash-mining. A modified yeast, added to wastewater treatment plants as an add-on to the bacterial sludge to desalinate the wastewater would solve this issue.

Looking for Industrial Applications

To investigate whether the wastewater pollution with NaCl is a problem only related to potash-mining or rather a common problem of industrial wastewaters we got into contact with the Chemelot Industrial Site located in the Netherlands. We visited Chemelot’s biological wastewater treatment plant.

We realized that wastewater pollution is not restricited to NaCl, whereas the variety of ions and molecules causes problems. The specificity of biological transporters makes yeast suitable to be a diverse microbial supercollector for these various pollutants, being highly interesting for industrial applications. To prove that the concept derived from this cooperation works, we expanded our project and integrated transporters for the sequestration of potassium and sulphate into a novel yeast mutant.

Investigating Supporting Methods

A supercollector needs supporting methods to make it feasible. Research and discussion have identified breeding, water separation and after-usage of the yeast as questions to be answered.

To investigate possible solutions on these issues we got into contact with the WVER (Water Association Eifel-Rur), which is responsible for water treatment in the region around Aachen.

Together with the WVER we concluded that a separation of desalination and conventional water treatment steps is needed due to competition between yeast and bacteria. Nutrition of the yeast directly in the wastewater would reduce costs. Therefore, we will carry out our further experiments and measurements directly in media containing salt. The yeast can be reused for enhanced gas production during fouling of the activated sludge and burned afterwards, leaving behind dry salt. Membrane technology developed to be interesting for us to separate yeast from the treated water, resulting in the cooperation with the RWTH Institute for sanitary environmental engineering.

Evaluation of Membrane Technology

The separation of yeast from water via membranes is promising to guarantee biosafety of our approach. We plan to integrate a membrane module into a possible application plant, however, question on the application and energy-efficiency of membrane modules remained unsettled after our research and talking with municipal wastewater plants. To gain more insight on the feasibility of this technology and answer the remaining questions we contacted the RWTH Institute for Sanitary environmental engineering.

Membrane Technology resulted to be best suited for our application because of the energy-efficiency of modern membrane modules and the capability of membranes to guarantee a total separation of microorganisms from water. However an experiment to prove the capability of membranes to do so is meaningful, resulting in our cooperation with General Electric.

Realization of Membrane Technology

Cooperations revealed the capability of membrane technology to hinder our modified yeast from spreading into the environment. Together with GE we set up a continuous experiment to separate yeast from water in small-scale using an ultrafiltration-membrane with field of application in wastewater treatment. The experiment proved complete separation of water and yeast cells with negligible efforts in maintenance and energy.

Final System

Together with our cooperation partners we were able to develop a novel system of biological wastewater treatment. With input from citizens we identified the problem of industrial wastewater salinization. After talking to industries, we expanded our project and proved the vacuolar uptake of ions in general with the sequestration of potassium. And with the help of water treatment researchers and industries we developed a system, finding solutions on nutrition, separation and after-usage of the yeast and proved the separation of yeast and water under realistic conditions.

Shaping Politics

Talking about environmental issues means talking about environment protection, a highly political topic, a trade-off between environmental action and the wealth of industries and their employees. For us taking environmental action always means shaping politics as well. During our iGEM project, we were confronted with various statements from industries, researchers or students on issues related to political environmental protection. To investigate and critically discuss the mentioned statements we talked to politicians and confronted them with our impressions. We implemented their answers on the current state of environmental protection in Europe and biological education in Germany into our project development.


I. Knowledge of high school students on genetic engineering is too low to have a differentiated position about it. Northrhine-Westfalian biological education seems to be outdated.

II. Genetic engineering is mainly ill-reputed in Germany and most political parties oppose the use of genetic engineering, however, high school and university students and researchers appreciate genetic engineering in the context of treating polluted wastewaters, raising the question if German politicians are close-lipped towards novel technologies?

III. If thresholds of water pollutions are exceeded, municipal wastewater plants are powerless to treat the water successfully. However, industries, for example in the Werra, are in parts allowed by law to exceed the thresholds, causing Germany to be complained by the European Union.

IV. Dutch industrials mark Germany as being more focused on industry than on environmental protection, concluding for example in high amounts of pollutions in the Dutch part of the river Rhine, all caused by Germany. Is environmental protection, especially water protection neglected in Germany?


I. Giving students basic principles to reflect their opinion on genetic engineering differentiated, is an eligible approach. However, schools have to cope with unmotivated teachers and missing trainee teachers, making changes to the curriculum difficult to implement in classrooms.

II. Genetic engineering, especially green genetic engineering, is seen rather critical by politicians from different political orientations. However, they display themselves as being open to novel technologies.

III. Water protection is regulated EU-wide with the power to complain countries not meeting the regulations and the power to put pressure on multinational companies.

IV. Politicians need to find a small line between environmental protection, industrial interests, protection of employment, public opinion and differing political parties, making decisions on environmental protection difficult, even if wished.

V. Significant environmental actions depend on comprehensive societal support. Societal debates are rare in present Germany, making it difficult for environmental politicians to implement important and innovative ideas.

VI. To implement a rational and not emotional, prejudiced debate on genetic engineering and environmental action, societal change must occur by for example providing good solutions on significant problems with the help of genetic engineering. Dialogue with society emerges as important for every biotechnical and environmental project.
We thank the following politicians from three different political parties, ranging from the middle-left to the right specter of Germany's political landscape, for talking to us and giving us answers to our questions. 
Andre Stinka and Mr Riegert, SPD, Northrhine-Westfalia Committee for environment

Dr. Patricia Peill, CDU. Northrhine-Westfalia Committee for environment
Dr Chrisitian Blex, AfD, Northrhine-Westfalia Committee for environment
Kristin Korte, CDU, Northrhine-Westfalia Committee for education