Biofuels are attractive substitutes for petroleum based fuels. Biofuels are considered they do not contribute to global warming in the sense they are carbon-neutral and do not increase carbons on the globe. Hydrocarbons that are synthesized by microorganisms have potential of being used as biofuels or the source compounds. In the hydrocarbon compounds synthesized by A. oryzae, fatty acids and triglycerides are the source compounds of biodiesel that is fatty acid methyl ester. We have increased the production by modifying fatty acid metabolism with genetic engineering in A. oryzae. Firstly, enhanced-expression strategy was used for the increase. For four enzyme genes related to the synthesis of palmitic acid [C16:0-fatty acid], the individual enhanced-expression mutants were made. And the fatty acids and triglycerides in cytosol were assayed by enzyme assay kits, respectively. As a result, both fatty acids and triglycerides were most synthesized in the enhanced-expression mutant of fatty acid synthase gene at 2.1-fold and 2.2-fold more than the wild-type strain, respectively. Secondly, gene disruption strategy was used for the increase. Disruptants of several enzyme genes related to long-chain fatty acid synthesis were made individually. And one of them showed drastic increase in fatty acid synthesis. In the future, further increase in the synthesis is expected by utilizing genetic engineering in A. oryzae.
Full conference title:
27th Fungal Genetics Conference
- Fungal Genetics Conference 27th (2013)