Glycerol conversion into a single cell oil by engineered Yarrowia lipolytica

Area of Science:

• Biotechnology
• Microbial Engineering
• Synthetic Biology

Background:

• Oleaginous yeasts are natural producers of single-cell oils.
• Engineering lipid biosynthesis pathways can enhance lipid accumulation in yeasts.
• Yarrowia lipolytica utilizes three diacylglycerol acyltransferases (Lro1p, Dga1p, Dga2p) in lipid formation.

Purpose of the Study:

• To engineer Yarrowia lipolytica for enhanced lipid accumulation.
• To reconstruct the triacylglycerol synthesis pathway by overexpressing DGA2.
• To evaluate the lipid production capabilities of the engineered strain JMY3580.

Main Methods:

• Construction of strain JMY3580 by overexpressing DGA2 in a quadruple deletion mutant (dga1Δ dga2Δ lro1Δ are1Δ).
• Cultivation of yeast on a glycerol-based medium with a high carbon to nitrogen ratio (90).
• Fed-batch cultivation with glycerol addition to further enhance lipid accumulation.

Main Results:

• Engineered strain JMY3580 accumulated over 40% lipids in biomass, compared to <20% in wild-type.
• Lipid accumulation exceeded 50% in fed-batch cultures with glycerol addition.
• Maximal biomass yield reached 18.5 g/L at 144 h, with a total fatty acid yield of 9.9 g/L.
• Altered fatty acid composition observed, with a lower percentage of linoleic acid in JMY3580.

Conclusions:

• Overexpression of DGA2 in Yarrowia lipolytica significantly enhances single-cell oil production.
• Engineered Y. lipolytica is a promising platform for microbial oil production from glycerol.
• The microbial oil produced has potential applications in various value-added products.