Metabolic engineering for isopropanol production by an engineered cyanobacterium, Synechococcus elongatus PCC 7942, under photosynthetic conditions.

Cyanobacteria engineered for production of biofuels and biochemicals from carbon dioxide represent a promising area of research in relation to a sustainable economy. Previously, we have succeeded in producing isopropanol from cellular acetyl-CoA by means of Synechococcus elongatus PCC 7942 into which a synthetic metabolic pathway was introduced. The isopropanol production by this synthetic metabolic pathway requires acetate; therefore, the cells grown under photosynthetic conditions have to be transferred to a dark and anaerobic conditions to produce acetate.

Quantitative target analysis and kinetic profiling of acyl-CoAs reveal the rate-limiting step in cyanobacterial 1-butanol production.

Cyanobacterial 1-butanol production is an important model system for direct conversion of CO to fuels and chemicals. Metabolically-engineered cyanobacteria introduced with a heterologous Coenzyme A (CoA)-dependent pathway modified from species can convert atmospheric CO into 1-butanol. Efforts to optimize the 1-butanol pathway in PCC 7942 have focused on the improvement of the CoA-dependent pathway thus, probing the in vivo metabolic state of the CoA-dependent pathway is essential for identifying its limiting steps.

New Insight into the Role of the Calvin Cycle: Reutilization of CO2 Emitted through Sugar Degradation.

Ralstonia eutropha is a facultative chemolithoautotrophic bacterium that uses the Calvin-Benson-Bassham (CBB) cycle for CO2 fixation. This study showed that R. eutropha strain H16G incorporated (13)CO2, emitted by the oxidative decarboxylation of [1-(13)C1]-glucose, into key metabolites of the CBB cycle and finally into poly(3-hydroxybutyrate) [P(3HB)] with up to 5.

Molar-based targeted metabolic profiling of cyanobacterial strains with potential for biological production.

Recently, cyanobacteria have become one of the most attractive hosts for biochemical production due to its high proliferative ability and ease of genetic manipulation. Several researches aimed at biological production using modified cyanobacteria have been reported previously. However, to improve the yield of bioproducts, a thorough understanding of the intercellular metabolism of cyanobacteria is necessary.