Metabolic engineering of cyanobacteria has received attention as a sustainable strategy to convert carbon dioxide to fatty acid-derived chemicals that are widely used in the food and chemical industries. Herein, Synechococcus elongatus PCC 7942, a model cyanobacterium, was engineered for the first time to produce fatty acid ethyl esters (FAEEs) from CO2. Due to the lack of an endogenous ethanol production pathway and wax ester synthase (AftA) activity in the wild-type cyanobacterium, we metabolically engineered S. elongatus PCC 7942 by expressing heterologous AftA and introducing the ethanol pathway, resulting in detectable peaks of FAEEs. To enhance FAEE production, a heterologous phosphoketolase pathway was introduced in the FAEE-producing strain to supply acetyl-CoA. Subsequent optimization of the cyanobacterial culture with a hexadecane overlay resulted in engineered S. elongatus PCC 7942 that produced photosynthetic FAEEs (10.0 ± 0.7 mg/L/OD730) from CO2. This paper is the first report of photosynthetic production of FAEEs from CO2 in cyanobacteria.
Bibliographical noteFunding Information:
This work was financially supported by the Korea CCS R&D Center (KCRC) (Grant 2014M1A8A1049277) funded by the Korean government (Ministry of Science, Information and Communications Technology (ICT) & Future Planning). Also this work was partially supported by a Golden Seed Project (213008-05-1-WT911) grant funded by the Ministry of Agriculture, Ministry of Oceans and Fisheries.
© 2017 American Chemical Society.
- CO conversion
- fatty acid ethyl ester
- metabolic engineering
ASJC Scopus subject areas
- Agricultural and Biological Sciences(all)