The ratio of hydrogelator to precursor controls the enzymatic hydrogelation of a branched peptide

Here, we report an apparently counterintuitive observation, in which a lower volume fraction of a branched peptide forms a stronger hydrogel after an enterokinase (ENTK) cleaves off the branch from the peptide. By varying the ratios of the branched peptide and ENTK and analysing the ratio of hydrogelator to precursor (H/P) in the enzymatic proteolysis reaction, our study shows that the H/P ratio controls the critical strain of the hydrogel formed, through enzymatic cleavage of the branch from the peptide. This work demonstrates that emergent properties (e.g., hydrogelation) of peptide assemblies, resulting from enzymatic noncovalent synthesis (ENS), are context-dependent, while also providing insights for developing dynamic soft materials via ENS.