The observation of substantial Rubisco activity in B. napus seeds 5, 7 indicates that the reassimilation of CO 2 by the Calvin cycle might explain the increased efficiency of carbon use.

Although not photosynthetic, some archaea possess RuBisCO, one of the enzymes characteristic of the photosynthetic Calvin-Benson cycle, but apparently lack another one, phosphoribulokinase (PRK ...

But no one explained to us exactly how that happened. It seems a protein called rubisco is what causes this to happen, but unfortunately it isn’t very picky.

After initial attempts at tweaking the RuBisCo enzyme directly to increase its affinity for carbon-dioxide were less than successful, focus during the 1990s shifted to understanding and optimizing.