Fig. 2

Domain size and organization affects molecular persistence. a Proteins with different propensities towards economy (E), flexibility (F) or robustness (R) will find optimal trade-off solutions given matter-energy budget and information. b Molecules segregate along a budgetary axis (left panel) in the order A’, A, AB and ABC, where letters indicate their domain makeup. The length of A’ is smaller than that of A. Larger proteins are more expensive to make and maintain but provide flexibility and robustness benefits. Once an information flux is made explicit (right panel) the segregation transforms into a triangle that unfolds trade-off relationships between flexibility and robustness. The extended vertex of flexibility is mainly driven by new levels of structural organization, such as the combination of domains in proteins, formation of quaternary structures and emergence of protein complexes. These levels impose additional constraints on economy that are always satisfied by the MA law at different levels of the hierarchy