August 1, 2012.
Ethylene is the most widely produced petrochemical feedstock globally. It is currently produced exclusively from fossil fuels through petroleum fractionation, the largest CO₂-emitting process in the chemical industry. In this study, the efe gene encoding an ethylene-forming enzyme was expressed in Synechocystis sp. PCC 6803, leading to continuous ethylene production. By optimizing concentrations of key nutrients in the media of Synechocystis, we achieved a better understanding of the limiting nutrients that lead to optimal ethylene bioproduction. Using response surface methodology, we determined that major nutrients found in the standard Synechocystis media—NO₃⁺, PO₄³⁻, SO₄²⁻, Ca⁺, Mg⁺, and HCO₃⁻—are required for optimal growth, suggesting that ethylene production is strongly correlated with general growth.
Jianping Yu, Justin Ungerer
National Renewable Energy Laboratory (NREL)
This material is based upon work supported by the S.D. Bechtel, Jr. Foundation and by the National Science Foundation under Grant No. 0952013 and Grant No. 0833353. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the S.D. Bechtel, Jr. Foundation or the National Science Foundation. This project has also been made possible with support of the National Marine Sanctuary Foundation. The STAR program is administered by the Cal Poly Center for Excellence in Science and Mathematics Education (CESaME) on behalf of the California State University (CSU).