Glycerol conversion into a single cell oil by engineered Yarrowia lipolytica

Abstract

Oleaginous yeasts are considered as natural single cell oil producers. Engineering the lipid biosynthetic pathway has the potential to increase lipid accumulation by these yeasts. In Yarrowia lipolytica, three diacylglycerol acyltransferases encoded by LRO1, DGA1, and DGA2 genes are involved in lipid formation. Strain JMY3580 was constructed by overexpressing DGA2 gene in Q4 strain (dga1Δ dga2Δ lro1Δ are1Δ). Reconstruction of triacylglycerol synthesis pathway led to significant improvement in lipid accumulation. Strain JMY3580 accumulated over 40% of lipids in biomass, while lipid accumulation in wild‐type strain was not able to exceed 20% when grown on a glycerol‐based medium with carbon to nitrogen ratio of 90. Higher lipid accumulation (over 50%) was achieved in fed‐batch grown cells when glycerol was added during cultivation. The best biomass yield was 18.5 g/L after 144 h with total fatty acid yield 9.9 g/L. Fatty acid composition was altered when Dga2p was the only diacylglycerol acyltransferase present in yeast cells, especially lower percentage of linoleic acid was present in lipids of JMY3580. Microbial oil prepared by conversion of glycerol by genetically engineered Y. lipolytica could be applied for various value‐added products based on single cell oils.

Engineering Yarrowia lipolytica for Enhanced Production of Lipid and Citric Acid

“…For lipid production in the shake flask and bioreactor, previous data on glycerol based fermentation media was taken into account, followed by some modifications [19,29]. The medium was formulated as follows: 1.…”

Lipid Production by Yarrowia lipolytica B9 Using Crude Glycerol as Carbon Source

“…The lipid content of the yeast was determined to be 60.1% under optimized culture conditions. This value was higher than the lipid contents of other Y. lipolytica strains which were cultivated in glycerol-based medium in the previous studies (Sriwongchai et al, 2013;Rakicka et al, 2015;Sara et al, 2016;Gajdoš et al, 2017;Niehus et al, 2018). Furthermore, it was higher than lipid contents of other oleaginous yeasts in the previous studies (Karatay & Donmez, 2010;Amaretti et al, 2010;Gao et al, 2017;Uprety et al, 2017).…”

Elevating Phospholipids Production Yarrowia lipolytica from Crude Glycerol

“…Therefore, the C/N ratio is important in determining the lipid content and biomass number of oleaginous microorganisms. According to many studies conducted in this field, the C/N ratio not only affects lipid accumulation but is also a strain-dependent factor for the Y. lipolytica [21]. Related to strain differences, the choice of a good carbon source is also of high importance [22].…”