Fig. 6.

Comprehensive redesign of the process that is associated with the FMA. A primordial state of the process might be reconstructed by, for instance, comparing anoxygenic bacterial and oxygenic photosynthesis (upper panels). From this primordial process, an alternative version of the process to be replaced can be constructed in a step-wise manner, employing genetic engineering, as well as in vitro approaches using libraries of suitable compounds (middle panels). If a suitable primordial process cannot be reconstructed or is already flawed, the process might be re-designed from scratch, requiring deep knowledge of the original process (bottom panels)