Metabolic engineering and synthetic biology for green chemistry

Since the 19th century, our societies have developed on the basis of flourishing industry, and have become dependent on products and energy from non-renewable sources. With environmental degradation and the imminent exhaustion of a large number of natural resources, we need to rethink our modes of production and consumption, starting with the economy, and then substituting essential needs with clean, sustainable alternative production.

The identification of natural strains enabled the development of the first industrial fermentation processes in the mid-twentieth century, with the production of antibiotics, amino acids and a few organic acids. Since the 1980s, however, advances in life science engineering have enabled us to go a step further, with the ambition of building "à la carte" organisms capable of producing the desired compound by fermentation from plant biomass resources. This is the aim of a field of research known as "metabolic engineering". To date, the fermentation of more than 130 different compounds has been studied in multiple organisms, with the aim of meeting the needs for fuels, plastics and other molecules in agriculture, chemistry and medicine (see the article [BIO801] in Techniques de l'ingénieur).

Forcing a micro-organism to produce a chemical compound is far from an easy task. It is possible to produce small quantities, but achieving an economically viable yield is highly dependent on the carbon source chosen, the scale of production and the separation method used. In this article, we present a range of tools and methods that can be used to design an organism and significantly increase its yield using synthetic biology approaches.

We believe that technologies derived from metabolic engineering and synthetic biology are soon ready to move out of the academic world and be experimented with more widely on an industrial scale, as shown by a number of recent industrial successes. We will also discuss the role of academic players and companies, as well as the development phases and tips for moving from the laboratory to the production fermenter.