Table 1.
IP20 Analogs developed as potential pseudosubstrate inhibitors for the catalytic subunit of Protein Kinase A (PKA-C) and summary of measured binding affinities (KD, [nM]) of peptides towards the human PKA catalytic isoforms Cα and Cβ1 as measured by fluorescence polarization (FP). Mean values of three independent measurements are given.
| Compound | Sequence 1 | Cα | Cβ1 |
|---|---|---|---|
| PKI5–24 | TTYADFIASGRTGRRNAIHD | n.d. 2 | n.d. 2 |
| 1 | βA-TTYADFIASGRTGRRNAIHD | 0.7 ± 0.1 | |
| 2 | βA-TTY*DFI*SGRTGRRNAIHD | 5.2 ± 0.3 | |
| 3 | PEG3-TTYADFIASGRTGRRNAIHD | 0.8 ± 0.1 | |
| 4 | PEG3-TTY*DFI*SGRTGRRNAIHD | 5.4 ± 0.9 | |
| PKI1–24 | TDVETTYADFIASGRTGRRNAIHD | n.d. 2 | |
| 5 | βA-TDVETTYADFIASGRTGRRNAIHD | 0.4 ± 0.1 | 0.4 ± 0.1 |
| 6 | βA-TDV*TTY*DFIASGRTGRRNAIHD | 0.6 ± 0.1 | 0.8 ± 0.3 |
| 7 | PEG3-TDVETTYADFIASGRTGRRNAIHD | 0.5 ± 0.1 | 0.5 ± 0.1 |
| 8 | PEG3-TDV*TTY*DFIASGRTGRRNAIHD | 0.7 ± 0.2 | 0.9 ± 0.3 |
1 Stars represent positions where 2-(4′-pentenyl) alanine was inserted into the sequence. 2 n.d.–not determined.