They are unicellular, abundant in nature and feel right at home in the most challenging conditions. We are referring to prokaryotes, single-celled bacteria that are comfortable with toxic substances and other extremes. Which mechanisms do these micro-organisms deploy to survive? And can we use them to breakdown harmful substances in nature and production processes?
“Micro-organisms are already regularly being used for bioremediation: a natural method to clean pollution,” says personal professor Hauke Smidt of Wageningen University & Research. “Examples include oil pollution at sea and cleaning toxic substances from the soil. The idea is that adding micro-organisms to nature helps break the toxins down faster. Unfortunately, this doesn’t always work well as the added organisms are often unsuited to the conditions to which they are exposed.”
Selecting and stimulating micro-organisms
At the invitation of Science, Hauke Smidt and colleagues from Wageningen and outside the Netherlands wrote an article which was recently published in the magazine. It provides an overview and evaluation of existing research. The result: prokaryotes use certain mechanisms to protect themselves against extreme conditions, such as the presence of toxins, high temperatures and excessive pH values. At the same time, the micro-organisms develop transformation and breakdown routes with which to battle pollution. “The trick is to select cultures of suitable micro-organisms that can easily be stimulated so that they can naturally break down specific types of pollution,” Smidt explains.
Prokaryotes in industrial processes
While the use of bacteria as pollution cleaners in nature sounds promising, the possibilities reach much further according to Smidt: “Imagine, for instance, that prokaryotes could be used in industrial production processes as well. Wageningen University & Research is part of BE-Basic, a large-scale national research programme in which we are looking for biobased solutions for a sustainable society. Another focal point of the programme is opportunities for businesses to integrate biotransformation within their production processes.”
Integrating new processes
“What the industry needs now are demo projects,” adds Smidt. “Take the production of bioplastics and biofuels, where we see increasing production flows developing, along with the related waste flows. Innovative solutions are required to break down or reuse the waste products released in these processes in a sustainable way. In fact, we should be proactively looking into how we could use micro-organisms as cleaners for every new production process. Although it won’t be the only technology available and may not be directly applicable in every process, I think the industry will find this technology indispensable in the future.”