Cyanobacteria are photoautotrophic prokaryotes, so researchers think they can naturally lower atmospheric CO2 levels. Research led by Bharat Kumar Majhi has shown that they can produce ethanol.
Photosynthetic organisms perform oxygenic photosynthesis to reduce CO2 into organic chemicals. These organic chemicals are utilized to produce biofuels. However, the procedure of biofuel production through fermentation is expensive and time-consuming.
Therefore, algae and cyanobacteria are being used as potential sources for biofuel production. With their photofermentation ability, they can directly convert CO2 to ethanol. Still, their natural ethanol production rates remain low, which hinders its wide applications.
Researchers have tackled this limitation by genetically modifying cyanobacterial strains to boost ethanol production rates. The team selected Synechocystis sp. PCC 6803 to inject genetic codes that are essential in ethanol biosynthesis.
“Though cyanobacteria have the potential to be a photosynthetic cell factory for producing a variety of biofuels, highly efficient strains for faster growth and higher product yield, optimized protocols and techniques for downstream processing, and the use of nanotechnology will be valuable assets.” the lead author included in the study.
Carbon Dioxide Can Be Used to Create Ethanol
Through these genetic modifications, scientists successfully reduced carbon wastage by diverting glycogen synthesis to ethanol production. Additionally, the adaptations to varied light and temperature were also induced to further elevate productivity.
By limiting carbon flux toward glycogen synthesis, the modified cyanobacteria produced 0.24 and 3.8 g/L of ethanol over 7–10 days. Also, the engineered cyanobacteria demonstrated consistent production in diverse environmental conditions.
The research used a fresh approach by rerouting carbon flow and overexpressing targeted enzymes. This study, published in the Journal of Bioresources and Bioproducts, highlights the importance of tailored genetic and metabolic strategies for fuel production.
While the use of the prokaryote in fuel production is a pivotal advancement, the large-scale exhibition and cost-efficiency still persist. Experimenters eye on the future researchers to bypass these limitations.
More Sustainable Way To Make Fuel Additive Ethanol
Journal Reference
- Majhi, B. K. (2024). Cyanobacteria: Photosynthetic cell factories for biofuel production. Journal of Bioresources and Bioproducts. DOI: 10.1016/j.jobab.2024.10.001
