French team success in iGEM Synthetic Biology Competition

« […] The French project: A “multicellular bacterium”
  The principal usefulness of the organism conceived by the French students resides in its ability to separate the expression of a foreign gene or transgene from the reproduction of the organism. Thus it opens up the field of production substances which are toxic for cell division. The expression of transgenes by bacteria in bioreactors has become a classical method for the production of molecules such as insulin. However, in many cases the synthesis of the desired compound is toxic for the bacterium. This limits the yield, because it is necessary to find a compromise between the growth of the bacteria and production of the desired substance. On the other hand, in this new bi-cellular organism, if only the “somatic” cells express the transgene, one should theoretically be able to achieve concentrations in these cells which are much higher than those obtained in classical expression systems. Of course there is always an equilibrium between growth and the production of a toxic substance. In fact, this compound should neither prevent the somatic cells from nourishing germinal cells, nor poision the latter by diffusing too readily. However, in the French team’s novel system, this equilibrium is shifted toward higher production in comparison to classic systems.
  Another application involves using somatic cells for the expression of a transgene outside the laboratory with no risk of escape into the environment. It is easy to induce differentiation of all the cells of the multicellular bacterium into somatic cells which are incapable of proliferation, but can continue to grow for several hours by forming long filaments. A potential application would be the storage of triglycerides in inclusion bodies of the somatic cells. These cells could be ingested during meals and would absorb the fat present in food. This project, called “Diet Coli”, (after “Diet Cola”), can be realized by expressing the enzyme DGAT (diacylglycerol acyltransferase) . The team has shown that the expression of DGAT from Acinetobacter ADP1 (5) in E. coli does indeed induce the synthesis of triglycerides, and in increased amounts if faty acids are present in the media. […] »

Extract from the article :

« Succès de la première équipe française lors de la compétition iGEM de biologie synthétique »
  David Bikard, François Képès, au nom de l’équipe iGEm Paris
  Médecine/Sciences 2008 ; 24 :541-4

Simulated creation by MGS of a multicellular bacterium: red cells divide and differentiate into green cells. In nature, bacteria are always monocellular.

For more information: :

• E-mail of Genoscopian contestants: nemoatgenoscope.cns.fr

• INTERNET SITES:
   Poster and press release:
   Site for the “Metabolic networks” group, to which the 4 Genoscopians belong: » à lequel appartiennent les 4 Genoscopiens
   Official site of the iGEM competition: de la compétition iGEM
   Webpage of the Francilian team on the official site:
   iGEM site in Europe:
   Site of the French virtual synthetic biology laboratory:
   CRI synthetic biology website:
   French synthetic biology site for the general public:

• OTHER ARTICLES ON THIS SUBJECT:
   "A scientific club for the creation of new forms of life " de Annie Kahn, Le Monde, 13/01/2008.
   "Un plan pour une révolution microbienne, des étudiants français récompensés par le MIT pour la conception d’un «organisme bactérien multicellulaire», de C.Bn, Libération, 29/01/2008 .
   "BIOLOGIE SYNTHÉTIQUE, la France à l’honneur", de David Larousserie, Nouvel Observateur, 29/11/07.
   “Un projet de biologie synthétique en trois mois d’été” de Dominique Chouchan, La Recherche, mai 2008.