  In this work it is shown that scale free tails in metabolic flux
distributions inferred from realistic large scale models can be simply an
artefact due to reactions involved in thermodynamically unfeasible cycles, that
are unbounded by physical constraints and would be able to perform work without
expenditure of free energy. After correcting for thermodynamics, the metabolic
space scales meaningfully with the physical limiting factors, acquiring in turn
a richer multimodal structure potentially leading to symmetry breaking while
optimizing for objective functions.
