Before revision:   Protein-protein electrostatic interactions are modulated by relative permittivity, which in general depends on protein concentration in the aqueous medium .
After revision:  Further elucidation will be necessary, however, especially of phenylalanine's role in condensate assembly because experiments on FtoA and YtoF mutants suggest that LLPS-driving phenylalanine interactions are significantly weaker than those posited by common statistical potentials. Protein-protein electrostatic interactions are modulated by relative permittivity, which in general depends on protein concentration in the aqueous medium .