Improving carbon fixation pathways

► Biological carbon-fixation is an important part of energy sustainability efforts. ► Calvin cycle improvement to arise by engineering neglected rate-limiting pathways. ► Synthetic biology offers new approaches to improve photosynthetic efficiencies. ► Alternative/synthetic carbon fixation routes are emerging as industrially relevant. A recent resurgence in basic and applied research on photosynthesis has been driven in part by recognition that fulfilling future food and energy requirements will necessitate improvements in crop carbon-fixation efficiencies. Photosynthesis in traditional terrestrial crops is being reexamined in light of molecular strategies employed by photosynthetic microbes to enhance the activity of the Calvin cycle. Synthetic biology is well-situated to provide original approaches for compartmentalizing and enhancing photosynthetic reactions in a species independent manner. Furthermore, the elucidation of alternative carbon-fixation routes distinct from the Calvin cycle raises possibilities that novel pathways and organisms can be utilized to fix atmospheric carbon dioxide into useful materials.