Why cutting respiratory CO2loss from crops is possible, practicable, and prudential

Plants release back to the atmosphere about half of the CO2they capture by photosynthesis. Decreasing the rate of crop respiration could therefore potentially increase yields, store more carbon in the soil and draw down atmospheric CO2. However, decreasing respiration rate has had very little research effort compared to increasing photosynthesis, the historically dominant metabolic paradigm for crop improvement. Conceptual and technical advances, particularly in protein turnover and directed enzyme evolution, have now opened ways to trim the large fraction of respiration that fuels proteome maintenance by lowering the breakdown and resynthesis rates of enzymes and other proteins. In addition to being theoretically possible and practicable, exploring the reduction of respiration is prudential, given that it (i) has barely yet been tried and (ii) could help meet the challenges of sustaining crop productivity and managing atmospheric carbon. Decreasing respiration is an under-explored way to sustain crop productivity and manage atmospheric carbon that synthetic biology may now enable by slowing needlessly fast turnover of enzyme proteins.