Industrial manufacturing produces lots of intermediate by-products. And the problem of industrial waste is a growing one. Decomposing these discarded substances usually takes a lot of resources, reaction plants… and the waste material has to be transported to the facilities. So, what can industry do about compounds that can’t be moved to be processed or are too expensive to get rid of? Synthetic biology can certainly be of help: bacteria are cheap to be grown and can be used to process the discarded compounds on-site. We have talked before about how to use bacteria to remove some industrial toxics, but today we want to tell you about a very specific case. The one we are facing at Rafts4Biotech: using bacterial rafts to design bacteria to degrade an industrial pollutant called TCP.
Let’s start with the basics: what is TCP and why should you care about it? TCP stands for 1,2,3-Trichloropropane, a complex molecule that has been used in the past as a varnish remover, industrial cleaning agent, or as an intermediate in some chemical reactions. It is also a non-desired by-product of many common chemical industrial processes. Just in the EU, more than 50 000 tons of this substance are produced, and its storage has become a problem for almost every country. The real problem comes when it’s not properly stored, and it leaks. Because TCP does not only contaminate the soil: it trickles down into groundwater reservoirs. And, once it reaches the water remnants, it stays at the bottom, since it is denser than water.
To face this environmental problem, we have taken a bioremediation approach: use biology to clean up waste.
To design bacteria that get rid of the TCP, we have tackled the challenge from scratch. First, our colleagues at Loschimdt Laboratories produced a microfluidic chip. Basically, it is a micronized laboratory that can automate the repetitive experiments researchers have to do on an everyday basis. Using this platform, they analyse the enzymes that can degrade the TCP, turning this molecule into CO2 and water. This first step has been a success: it not only has allowed us to understand the TCP degradation in detail, but we have created a tool that can be adapted to many other projects that need to automate fluidic experiments.
In the next months we will be facing the next challenge: integrating the genomic pieces of information onto actual bacteria, so they produce the enzymes in the right amounts and can munch on TCP. It’s the most crucial step. Luckily, we have a powerful ally on our side: the lipid rafts. These tiny areas in the outskirts of the bacteria will help bacteria produce the enzymes more efficiently. And since the rafts are on the membrane, separated from the central core of the organism, they will prevent them from getting poisoned by the TCP.
Once finished, this challenge could mean a significant step towards establishing bioremediation as a wide solution to managing industrial waste. Not only for TCP and the environmental menace it poses. The tools we have developed in the process are useful for a wide number of synthetic biology researchers that work on using microbes to produce a greener industry.