Centre for Engineering Biology

Could microbes be our smallest collaborators in biotechnology?

Microbes are more than tiny machines. Let’s see what we might learn from them, and even what we might accomplish together.

Synthetic biology, a developing area of research focused on designing and building with DNA, tends to attract attention for several reasons. Some synthetic biologists have engineered baker’s yeast and other microorganisms to produce such diverse products as vanilla flavouring, cow milk proteins, and spider silk. Others involved with the field are concerned that similar scientific strategies could be employed to produce biological weapons, a concern notably articulated in a recent report from the US National Academy of Sciences. And, in projects more inclined to incite human wonder and curiosity than concern about safety and the shape of global agriculture, landmark projects are redesigning complete genomes for bacteria and yeast to test longstanding scientific questions and, perhaps, to make even better living platforms for additional engineering.[i]

Whatever the focus, synthetic biology is usually about control. Scientists aim to understand how DNA sequences yield cellular functions so comprehensively that designing with DNA and building living cells with custom functions might not be much harder than designing and building with wood or steel—or, more aptly, with a programming language.

Achieving this level of control with living organisms is difficult. Synthetic biology has seen great success with pathways of several genes linked together to produce a specific molecule of interest or a very simple cell behaviour. More ambitious designs, however, rapidly slam into a problem: living cells are extraordinarily complex and there remains a great deal that we don’t yet know about them.

One response to that challenge is to work hard to more fully understand how cells hold together. Another response is to try to make “life” simpler by identifying the absolute basics a cell needs to survive and then building them from scratch using just those elements. But a third option—and maybe a more achievable one at least in the near-term—involves de-emphasizing control and working with living things to achieve design goals.

Yeast and bacteria—the microorganisms with which synthetic biologists do most of their work—are not wood and steel nor, for that matter, are they computer programs. A major distinguishing factor is responsiveness: living organisms change and respond to their surroundings and other organisms much faster than non-living materials. Synthetic biology projects often involve trying to dampen this tendency for living organisms to change so that cells do only what they are told and other cell activities don’t interfere with human designs.

Rather than trying to make living things more like non-living materials, however, another option involves working with cells’ abilities and propensities to accomplish something together in what you might call a 'multispecies collaboration.'

The synthetic yeast project, the first effort to build a complete eukaryotic genome entirely out of redesigned DNA, is applying this sort of approach toward building yeast genomes better adapted to survive stressful environments.

Working with living cells might be productive for scientists’ efforts to achieve design goals. But just as important is the shift in perspective toward other creatures that the idea of “multispecies collaboration” might engender.

Trying to control other creatures to serve human needs has tended to put the lot of us – humans, other species, and the planet – in massive trouble. Synthetic biology is often about trying to help get us out of that trouble by reducing our dependency on fossil fuels and devising more sustainable modes of production. Humans are recognizing that growing what we need may be a better option than mining, smelting, or burning. Simultaneously, however, we humans are increasingly attentive to the needs of non-humans, not only—but not least—because human wellbeing depends on the wellbeing of other species.

Microbial life may be easy to ignore because it’s small, but microorganisms are vitally important to the survival and wellbeing of all life. As we seek better ways to live in community with all of the inhabitants of this planet, human and otherwise, we might keep in mind that even our smallest companions have lives of their own, and seek to expand our capacity to work and communicate with them as living creatures rather than seeking only to increase our control over them. Microbes are more than tiny machines. Let’s see what we might learn from them, and even what we might accomplish together.

By Drs Erika Szymanski and Jane Calvert

Science, Technology & Innovation Studies, School of Social and Political Science, University of Edinburgh 

For more on Szymanski and Calvert's work, see https://www.nature.com/articles/s41467-018-05332-z



[i] See, for example, https://www.theguardian.com/science/2017/jan/23/organisms-created-with-synthetic-dna-pave-way-for-new-entirely-new-life-forms and https://www.theguardian.com/science/2017/mar/09/synthetic-yeast-genome-nearly-complete-paving-way-for-bespoke-organisms