Camelina sativa: An ideal platform for the metabolic engineering and field production of industrial lipids

Abstract

Triacylglycerols (TAG) containing modified fatty acids with functionality beyond those found in commercially grown oil seed crops can be used as feedstocks for biofuels and bio-based materials. Over the years, advances have been made in transgenically engineering the production of various modified fatty acids in the model plant Arabidopsis thaliana. However, the inability to produce large quantities of transgenic seed has limited the functional testing of the modified oil. In contrast, the emerging oil seed crop Camelina sativa possesses important agronomic traits that recommend it as an ideal production platform for biofuels and industrial feedstocks. Camelina possesses low water and fertilizer requirements and is capable of yields comparable to other oil seed crops, particularly under stress conditions. Importantly, its relatively short growing season enables it to be grown as part of a double cropping system. In addition to these valuable agronomic features, Camelina is amenable to rapid metabolic engineering. The development of a simple and effective transformation method, combined with the availability of abundant transcriptomic and genomic data, has allowed the generation of transgenic Camelina lines capable of synthesizing high levels of unusual lipids. In some cases these levels have surpassed what was achieved in Arabidopsis. Further, the ability to use Camelina as a crop production system has allowed for the large scale growth of transgenic oil seed crops, enabling subsequent physical property testing. The application of new techniques such as genome editing will further increase the suitability of Camelina as an ideal platform for the production of biofuels and bio-materials.

Expression of Camelina WRINKLED1 Isoforms Rescue the Seed Phenotype of the Arabidopsis wri1 Mutant and Increase the Triacylglycerol Content in Tobacco Leaves

“…Camelina has an advantage as an oil crop as it is amenable to metabolic engineering for the manipulation of vegetable oil biosynthesis (Bansal and Durrett, 2016). Metabolic engineering in Camelina is underway to modify the fatty acid composition by blocking the endogenous fatty acid desaturase 2 (FAD) and fatty acid elongase (FAE) 1 pathways, which would make it more suitable for biofuel (Nguyen et al, 2013), and to incorporate new pathways to produce unusual fatty acids for industrial uses (Snapp et al, 2014; Liu et al, 2015; Nguyen et al, 2015), and omega-3 long-chain polyunsaturated fatty acids for human consumption (Petrie et al, 2014).…”

“…Camelina has a relatively short growing period (85–100 days to maturity) and can be cultivated twice in 1 year (Putnam et al, 1993). In comparison with other oil crops, it requires lower amounts of fertilizer for growth and is more resistant to various stresses such as cold and drought (Putnam et al, 1993; Kim et al, 2013; Bansal and Durrett, 2016). Camelina seed oil is composed of 35–45% triacylglycerol (TAG), which has a high proportion of polyunsaturated fatty acids (PUFAs) (Lu and Kang, 2008; Bansal and Durrett, 2016).…”

Camelina Seed Yield and Fatty Acids as Influenced by Genotype and Environment

“…that involves vacuum infiltrating young inflorescences with an Agrobacterium suspension (floral dip transformation) also offers additional opportunities to create novel oil compositions useful for fuel and industrial applications (Bansal and Durrett, 2016). While the focus of camelina in the United States has been for biofuel production, camelina oil also possesses good nutritional qualities.…”

Two Acyltransferases Contribute Differently to Linolenic Acid Levels in Seed Oil

“…However, the interest in this plant is now reinvigorated due to its high potential for biotechnological applications. In recent years, C. sativa has emerged as a model crop plant for oilseed research and field-scale production (Feussner, 2015;Vollmann and Eynck, 2015;Bansal and Durrett, 2016;Berti et al, 2016). In addition to its history as an oilseed crop, the genetic similarity to the well-studied model species Arabidopsis (Arabidopsis thaliana; Kagale et al, 2014) and the ease of genetic transformation (Lu and Kang, 2008) have pushed C. sativa into the forefront of oilseed research and trait development.…”