Towards the Synthetic Design of Camelina Oil Enriched in Tailored Acetyl-Triacylglycerols with Medium-Chain Fatty Acids

The Science

To produce 3-acetyl-1,2-diacyl-sn-glycerols (acetyl-TAGs) with medium-chain fatty acids (MCFAs) in the oilseed crop Camelina sativa by metabolic engineering.

• Different transgenic camelina lines that had been genetically modified to produce MCFAs through the expression of MCFA-specific thioesterases and acyltransferases were retransformed with the Euonymus alatus gene for diacylglycerol acetyltransferase (EaDAcT) that synthesizes acetyl-TAGs.
• Concomitant RNAi suppression of acyl-CoA: diacylglycerol acyltransferase was designed to increase the levels of acetyl-TAGs.

The Impact

• Successfully generated metabolically engineered camelina that produce acetyl-TAG molecules containing medium-chain fatty acids.
• These tailored lipids with a designed structure are potentially useful for production of biofuels and bioproducts in crops such as sorghum.

Summary

The ability to manipulate expression of key biosynthetic enzymes has allowed the development of genetically modified plants that synthesise unusual lipids that are useful for biofuel and industrial applications. By taking advantage of the unique activities of enzymes from different species, tailored lipids with a targeted structure can be conceived. In this study researchers demonstrate the successful implementation of such an approach by metabolically engineering the oilseed crop Camelina sativa to produce 3-acetyl-1,2-diacyl-sn-glycerols (acetyl-TAGs) with medium-chain fatty acids (MCFAs).

References

Bansal, S., H. J. Kim, G. Na, M. E. Hamilton, E. B. Cahoon, C. Lu, T. P. Durrett. 2018. “Towards the Synthetic Design of Camelina Oil Enriched in Tailored Acetyl-triacylglycerols with Medium-Chain Fatty Acids,” Journal of Experimental Botany 69(18), 4395–402. DOI:10.1093/jxb/ery225.