‘Direct Conversion’: Artificial Photosynthesis With Cyanobacteria

Cyanobacteria, the only bacteria that can carry out oxygenic, (ie, plant-type) photosynthesis, can be engineered with the methods of synthetic biology so that they acquire the ability to convert CO2 directly into biofuel and/or commodity chemicals. In such an approach one bypasses the formation of the entire complex set of (macro)molecules that jointly form biomass. This approach has become known as ‘direct conversion’ (of CO2 and sunlight into biofuel) and has been shown to be feasible for several products already, even upon significant scaleup. Here we explain this concept of ‘direct conversion’ through natural photosynthesis and discuss its limitations and potential further improvement.