Researchers Engineer Ashbya gossypii for the Production of Microbial Oils

Ashbya gossypii is a fungus used for the industrial production of riboflavin. Its ability to grow in low-cost feedstocks, inexpensive processing and availability for genetic modifications make it a good subject for production. Recently, it has also been introduced as an ideal microbe for the production of microbial oils. However, it cannot consume xylose, a common pentose in hydrolysate of plant biomass.

Researchers from Universidad de Salamanca in Spain aimed to design A. gossypii strains capable of utilizing xylose as carbon source for the production of biolipids. A xylose utilization pathway in A. gossypii was identified and overexpressed, resulting in an A. gossypii xylose-metabolizing strain. Furthermore, metabolic flux increased the lipid content in the xylose-metabolizing strain by 54% over the parental strain growing in glucose-based media. It further increased to 69% when lipid accumulation was boosted by blocking the beta-oxidation pathway.

The results prove the production of microbial oils from xylose in A. gossypii. This introduces a new biocatalyst in the production of fine chemicals and biofuels from xylose-rich hydrolysates of plant biomass.