Fig. 4.
Darwin’s principle of multiple utility at the protein level. In maquette design red segments 1, 11 and 12 would be excluded, as initially would 5 and 6. Green segments 2, 3, 4 and 7 represent minimal utilities for the simplest maquette incorporating a bioinorganic cofactor; green/red segments 8, 9 and 10 represent catalytic utilities.