(A) Schematic of SrtA-mediated peptide cleavage. (B) Effect of alanine:glycine composition on softening of PEG8NB-A-G gels (3.0 wt% PEGNB, 25μM SrtA, & 12mM GGGGC). (C) Effect of SrtA concentration on softening of PEG8NB-A-G gels (50%A:50%G, 3.0 wt%, 12mM GGGGC). (D) Effect of initial PEG8NB concentration on softening of PEG8NB-A-G gels (50%A:50%G, 25μM SrtA, & 12mM GGGGC). (E) Effect of treatment time on softening (50%A:50%G, 3.0 wt%, 12mM, 25μM SrtA, and 12mM GGGGC).