Our fat-bulous project:

However, any large-scale production of rare fatty acids would necessarily lead to new plantation, and therefore environmental problems. The use of synthetic biology for production could help avoid a potential overexploitation of these plants. Protection of the environment is one of our objectives, one of the major issues of our time. We do not want to repeat the mistakes of the past. The exploitation of palm oil is sadly lucrative for the exploiter because of its high value. This problem applies equally well to Punica granatum and Jacaranda mimosifolia, that's why we chose those two for this project. We want to produce these rare fatty acids without having an adverse impact on the environment. Since these types of fatty acids are present in very small quantity in the plants, bio-production can be even more important to prevent large scale deforestation [8].

Our Synthetic biology project is therefore very adapted to deal with the problems of deforestation. Especially for projects that wish to exploit plants for industrials pharmaceuticals, agrofood and cosmetics. Indeed, bio-production through microorganisms requires less resources, less space for a proportionally higher yield. So our project would allow us to start developing alternatives to deforestation.

Our objective is to develop a platform for rare fatty acids bioproduction, in order to limit environment and economic problems in the long term. As a biological chassis, we will use yeast and especially oily yeast Yarrowia lipolytica because it is a species that has already proven its effectiveness for the production of fatty acids, thanks to its highly developed lipid metabolism. [9] [10] [11].

Yarrowia: an ideal chassis for fatty acid production

Generally speaking, the most widespread chassis in the field of synthetic biology is Esherichia coli. Indeed, its short generation time and easy culture conditions made E. coli the microorganism model for biological studies. Our great knowledge of E. coli makes it a chassis easy to manipulate and easily adaptable to different plasmid construction.

However, as part of our biomanufacturing project, we have chosen to use the yeast Yarrowia lipolytica. Our choice was motivated by several elements that make Yarrowia an ideal chassis for the bio-production of rare fatty acids also known as conjugated linoleic acids:

1) Yarrowia lipolytica is a GRAS organism (generally recognized as safe), so it is safe and easy to handle.

2) Yarrowia lipolytica has a metabolism capable of producing linoleic acid, which is the substrate for the synthesis of Conjugated linolenic acids (CLnA) we want to produce [11].

3) Yarrowia lipolytica is one of the rare oleaginous organisms capable of storing large amounts of fatty acids in its cytoplasm. Up to 40% of the cytoplasmic volume can be allocated to the storage of fatty acids [12].

However, Yarrowia lipolytica does not naturally produce the rare fatty acids we are interested in. So, we need to find the enzymes that allow the synthesis of these fatty acids. As a matter of fact, we were able to identify relatively easily the protein sequences of the enzyme catalyzing the formation of punicic acid from linoleic acid [13]. However, the search for enzymes that allow the synthesis of jacaric acid was harder. After a long search we have not been able to obtain this sequence, so we conclude that it is not known yet.

Therefore punicic acid synthesis could be used as a trial to prove the effectiveness of our design, before attacking the more troublesome case of jacaric acid. Our first objective is the elaboration of our production platform for synthesis of punicic acid. Our second objective is to prepare in parallel the baseline for the production of jacaric acid. Consequently, we wanted to find the enzyme that catalyzes the reaction of synthesis of jacaric acid. To do so, we decided to sequence the entire exome of the only tree known to date to produce this fatty acid, Jacaranda mimosifolia. Through bioinformatic analysis of the subsequent data, we will successfully determined the sequence of the missing enzyme.

References

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