Metabolic Engineering of Synechocystis sp. Leads to Improved Fatty Alcohol Production

The biosynthetic pathways for fatty alcohols are diverse and widely existing in nature. Previous studies have reported a Synechocystis sp. PCC 6803, engineered with a fatty alcohol-producing pathway, and produced a relatively low yield of fatty alcohols. Based on these results, scientists are developing a strain with improved fatty alcohol production.

The photosynthetic production of fatty alcohols in Synechocystis sp. PCC 6803 was improved through expression of the gene maqu_2220, derived from the marine bacterium Marinobacter aquaeolei VT8. The gene, Maqu_2220, has been proven to initiate the production of fatty alcohol. Aside from the work of Maqu-2220, the fatty alcohol yield was improved by silencing two other genes, sll0208 and sll0209, which are involved in hydrocarbon biosynthesis. This resulted in redirection of carbon from the hydrocarbon synthesis into the fatty-alcohol producing pathway, thus further increasing the fatty alcohol yield of the strain.

The highest yield of fatty alcohols was achieved in cyanobacteria by expressing the Maqu_2220 and knocking-out the two key genes involved in the hydrocarbon biosynthesis pathway. The production of fatty alcohols could be significantly increased further by blocking the whole hydrocarbon biosynthesis pathway.