Abstract
Though microalgae have been considered the potential resource for lipid production, native strains are unable to meet the industrial demand. Here, we aim to uncover the complex molecular relationship between algal growth and lipid accumulation. Transcriptomic analysis revealed the crucial role of plastidial fatty acid and triacylglycerol (TAG) biosynthetic machinery in lipid overproduction. The expression of key fatty acid biosynthetic genes such as acetyl-CoA carboxylase (ACCase), malonyl CoA‐acyl carrier protein transacylase (MCAT), 3-ketoacyl synthase (KAS), 3-ketoacyl-ACP reductase (KAR) increased during day 10-13 of cultivation, particularly plastidial TAG biosynthetic genes substantially increased. However, expression of genes involved in ER TAG biosynthesis increased only in the stationary phase, which implied the potential of plastidial TAG biosynthesis. This report provides a novel insight into the growth-phase dependent lipogenic orchestration, and also uncovers the signature genes and plastidial TAG biosynthesis that might be extrapolated for improving lipogenic traits of algae.
Highlights
Microalgae have emerged as the potential biological feedstocks for the sustainable production of a wide range of biocomponents including lipids, polyunsaturated fatty acids, vitamins, carotenoids, and recombinant proteins (Mata et al, 2010)
It is well known that algal cells involve in growth during log phase, whereas cells involve in energy metabolism in the stationary phase to meet the energy demand and for the cell survival under nutrient-deprived conditions (Yang et al, 2013). Various strategies such as nutrient deprivation, stress treatments, etc. have been used to increase algal lipid accumulation, these sub-optimal treatment methods resulted in reduced growth and impaired biomass accumulation
We found that genes involved in plastidial TAG pathway such as glycerol-3-phosphate acyltransferase (GPAT), lysophosphatidate acyltransferase (LPAAT), and diacylglycerol acyltransferase (DGAT) were remarkably higher on both day 10 and 13 (Figure 2A)
Summary
Microalgae have emerged as the potential biological feedstocks for the sustainable production of a wide range of biocomponents including lipids, polyunsaturated fatty acids, vitamins, carotenoids, and recombinant proteins (Mata et al, 2010). Considering the negative environmental and economic impact of fossil fuels combustion and rapidly depleting reserves have further attracted the research attention toward commercial exploitation of microalgal biofuel owing to their inherited beneficial characteristics (Chisti, 2007). Oleaginous microalgal species are gaining huge research interests due to their promising oleaginicity and possibilities of wide commercial applications (Han et al, 2017). Native strains do not hyperaccumulate biocomponents under optimal conditions, which extremely incumbers their commercial applications (Chisti, 2013). Algal cells have been shown to overproduce triacylglycerol (TAG), the critical precursor for biofuels under stress conditions which constrain the biomass and growth, thereby. It is of paramount significance to improve the genetic traits to produce algal biocomponents in a commercially feasible manner
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
