Table 2.
Catalytic Activity of VH1 toward pS/pT Peptides
| Peptide No | Peptide sequencea | kcat (s−1) | KM (mM) | kcat/KM (M−1 s−1) |
|---|---|---|---|---|
| 1 | YNDFAIpTAA | 0.4 ± 0.2 | 2.1 ± 1.0 | 180 ± 9 |
| 2 | YNAFAIpTAA | NDb | >2 | 93 ± 3 |
| 3 | YNDAAIpTAA | ND | >2 | 9 ± 1 |
| 4 | YNDFAIpSAA | 0.2 ± 0.1 | 2.3 ± 0.3 | 95 ± 10 |
| 5 | YEFFAGpTAA | 0.6 ± 0.1 | 0.8 ± 0.1 | 700 ± 16 |
| 6 | YAFFAGpTAA | ND | >0.5 | 350 ± 13 |
| 7 | YEFFANpTAA | 1.4 ± 0.1 | 2.9 ± 0.1 | 500 ± 7 |
| 8 | YEFFYGpTAA | ND | >0.5 | 1100 ± 37 |
| 9 | YNLLQNpTAA | 1.8 ± 0.1 | 4.6 ± 0.4 | 390 ± 18 |
| 10 | YEYQFNpTAA | 1.1 ± 0.1 | 1.2 ± 0.2 | 870 ± 18 |
| 11 | YNpTDFIQF | ND | >0.5 | 500 ± 23 |
| 12 | YNpTFDIQF | ND | >0.5 | 300 ± 24 |
| 13 | YNpTFSDFI | ND | >1 | 350 ± 9 |
| 14 | YNpTFIADF | 0.8 ± 0.1 | 0.8 ± 0.1 | 1020 ± 42 |
| 15 | YNpTFLIVE | 2.3 ± 0.5 | 0.6 ± 0.2 | 3800 ± 450 |
| 16 | YEYQFNpTDFIQF | 0.5 ± 0.1 | 0.03 ± 0.01 | 16300 ± 6600 |
a
All peptides contained an acetyl group at the N-terminus and a C-terminal amide. ND, kcat and KM values could not be accurately determined due to limited peptide solubility.