Fig. 3: Sequence-activity profiling of Pap2c_1 yields better binders in vivo.
From: Selection for constrained peptides that bind to a single target protein
a Schematic of Pap2c_1 peptide fusion used for in vivo measurements. Leader and core amino acids considered for profiling are displayed and predicted modified core residues highlighted in light blue. A fusion protein of the 39 amino acid ACE2α1 peptide to the C-terminal NpuC-σC was included as an off-target control. Dashed lines indicate the fluorescence output of the circuit driven by the RBD:PMI interaction measured in Fig. 1d. 3OC6-AHL (1 µM) was used for inductions and three replicates performed on different days are shown. b Heat map of variant enrichment from selection and NGS. Amino acid substitutions enriched relative to the parent sequence are colored red. c Fluorescence output of consensus variant strains constructed based on data from (b). Individually constructed variants at position -3 (A, I, L, V) were evaluated for fluorescence output of the circuit. 3OC6-AHL (0 µM) was used for inductions and three replicates performed on different days are shown. d Schematic of the Pap2c_1 peptide fusion used for in vivo measurements and TEV protease site insertion analysis. Modified core residues are shown in light blue. Dashed lines indicate the fluorescence output of the circuit driven by the RBD:PMI interaction measured in Fig. 1d. 3OC6-AHL (1 µM) was used for inductions and three replicates performed on different days are shown.
