Team:Uppsala Universitet/Human Practices
Integrated Human Practice
Universities, governments, private companies and organizations around the world are racing to find environmentally friendly solutions to meet rising global demand for energy and complex chemicals that are now coming from fossil fuels. This is because fossil fuels have a variety of negative effects on the environment: pollution, increased carbon dioxide levels and environmental destruction. Inspired by the unique natural resource that Sweden has, its forests, the Uppsala iGEM 2019 team wanted to contribute in some way in solving these problems. To make the dream of turning a crude paper-processing waste product into a valuable product a reality, we needed to engage with many different societal actors. We devised a three-pronged plan to focus our efforts on industry, academia and science entrepreneurs.
Industry Interactions
Our initial idea was to use the waste product, lignin from paper mills, as a substrate that our enzymes could break down into smaller components. However, many questions remained; what type of lignin was this "waste lignin"? How was lignin separated out? What goes into this separation? To gain a better understanding, we organized two field trips: one early in the summer to one of the largest paper-processing plants in Scandinavia, Stora Enso’s paper mill in Skutskär. There we were able to get a guided tour of the facilities where wood biomass is taken and processed to produce raw paper. Later, in the summer, we were able to tour Stora Enso’s state-of-the-art research facility in Sickla. From these trips, we took two main ideas that changed how we thought about our project:
- We realized the enormous scale at which biomass is processed, something that does not hit home until you stand in front of the 3 story piles of wood chips that we saw. In order for our project to truly make an impact, lignin degradation would have to occur at a much larger scale than at the experimental level. Therefore, we continually adjusted our project design to maximize efficiency and scaling ability. This includes choice of yeast strain, simplifying and eliminating steps in enzyme purification and using cheap materials that would translate to a larger scale. We also invested more time in learning about scaling up enzyme production by, for example, visiting the Testa Center, a laboratory built by General Electric which has facilities in which start-up companies and entrepreneurs can test their prototypes before scaling up.
- We learned that the paper industry has developed very specific and well-refined processes to separate out lignin. The result is a lignin that has different characteristics from lignin found in wood, and can vary depending on the process used for separation. For example, kraft lignin (produced from the Kraft process) and lignosulfonates (produced from the sulfite process) have different bond composition. Since our idea was to be the link between the paper industry and other companies that build up complex chemicals, we realized that we needed to test the effectiveness of our secreted enzymes on these lignin structures instead. As a result our Proof of Concept group worked exclusively with industrial produced lignins from Stora Enso and Domsjö.
Conversations with Researchers in the Field
Lignin degradation and protein engineering are two hot, but disparate topics within scientific research. In order to succeed with our project, we sought the advice of experts doing cutting edge research within these fields. To learn the details about how to effectively produce our active enzymes using a yeast as our cell factory, we reached out to professors at Uppsala and the Swedish Agricultural Universities to receive feedback on our project design. These experts in cloning in yeast, gave us advice on methods and conditions to maximize secretion levels, advised on which type of enzymes to use and what type of methods could be selected to introduce the synthetic DNA into these yeasts. It was through these discussions that we eventually settled on using P. Pastoris as our cell factory and HRP and AAO as our two main lignin degrading enzymes. We also needed to learn more about the complex polymer lignin. Once again, we were fortunate to discuss this topic with some of the foremost lignin researchers in the field at Kungliga Tekniska Högskolan and Uppsala University. After presenting and discussing our project with them, we adapted our proof of concept. They advised us to use specific chromatography techniques to assess the effect of our enzyme activity. When this turned out to be out of our budget, their further suggestions were key in what eventually became the techniques we used to visualize lignin degradation.
Discussions and Interviews with Science Entrepreneurs
At the beginning of the project, the team had difficulties in communicating the goal of our project effectively, especially to those who are not familiar with iGEM. Since we believed our project had potential in being applied industrially, we wanted to learn how to more effectively present our project so that businesses and the general public would be more interested in our work. As a result, we sought out some of the most innovative business leaders and developers in Sweden to interview and talk with them about entrepreneurship within the sciences. The overarching message from these entrepreneurs was to make the problem crystal clear and to address why our product is uniquely qualified to solve it. As a result, we adapted our message to focus more on the potential products that could be built from the degraded lignin that our system produces, and the positive impact it will have in addressing the important issues of our time. The audience as a result has had a clearer idea why our project was worth caring about, and have therefore become more engaged in our cause. In order to continue practicing this skill, we helped organize a prototype workshop in our collaboration with the Stockholm iGEM team during BioEntrepreneurship conference.
A responsible and useful project
We believe that a sustainable society can not afford to waste any potentially precious resources. Bearing this general idea in mind, we chose lignin as the object of our interest. Lignin is a complex component of wood, which carries hidden potential in its high content of aromatic rings. Given the location of our university and the unique resource that Sweden has in its forest, we are right in the middle of the impact area of our project! We carefully considered the potential of our project and weighed the risks. A wide range of useful products could be derived from the lignin degradation products, and maybe most importantly it has potential for the production of biofuels [1]. Since lignin waste is produced in such a high quantity, the production of carbon neutral biofuels based on lignin could become a consistent source of environmentally friendly fuel [2].
Our goal is to modify the yeast Pichia pastoris so that it expresses enzymes that break down lignin. In case of an escape of our modified organisms into the natural environment, one could imagine that this poses a threat to the forest. We thought carefully, discussed and eventually judged this risk to be low for three main reasons.
First, the enzymes produced by our engineered yeast would ultimately be used on dissolved lignin or lignin with a large surface area. They would most probably not work well in the environment.
Second, the ligninolytic organisms in nature are much better adapted to the forest niche than our engineered yeast or Escherichia coli cells would be. The enzymes we added to Pichia pastoris are naturally occurring and they are not harmful to the environment.
Third, in the unlikely event that the engineered organism escapes from the lab, it would not receive any fitness benefit from its genetically engineered enzymes. The continual production of unneeded proteins and the increased genome size even carry a small fitness penalty. Therefore, it should not be able to compete with natural ligninolytic organisms in nature.
The Roots of Human Practice
Just as a tree takes power through its roots, our project takes power from integrated human practice. Click on the text in the centre of the boxes of the root system of our time-line tree to learn more.
