|標題:||Metabolic engineering of cyanobacteria for the photosynthetic production of succinate|
|作者:||Lan, Ethan I.|
Wei, Crystal T.
Department of Biological Science and Technology
|關鍵字:||Cyanobacteria;Succinic acid;Carbon dioxide re-utilization;Bio-based production|
|摘要:||Succinate is an important commodity chemical currently used in the food, pharmaceutical, and polymer industries. It can also be chemically converted into other major industrial chemicals such as 1,4-butanediol, butadiene, and tetrahydrofuran. Here we metabolically engineered a model cyanobacterium Synechococcus elongatus PCC 7942 to photosynthetically produce succinate. We expressed the genes encoding for aketoglutarate decarboxylase and succinate semialdehyde dehydrogenase in S. elongatus PCC 7942, resulting in a strain capable of producing 120 mg/L of succinate. However, this recombinant strain exhibited severe growth retardation upon induction of the genes encoding for the succinate producing pathway, potentially due to the depletion of a-ketoglutarate. To replenish alpha-ketoglutarate, we expressed the genes encoding for phosphoenolpyruvate carboxylase and citrate synthase from Corynebacterium glutamicum into the succinate producing strain. The resulting strain successfully restored the growth phenotype and produced succinate with a titer of 430 mg/L in 8 days. These results demonstrated the possibility of photoautotrophic succinate production.|
|Appears in Collections:||Articles|