Table 2.
OsGNAT2 specific activity is similar to AtGNAT2 and displays unique features.
| Peptide substrate | Peptide length | Specific NTA activity (nmol.min−1.μmol−1)$ |
|---|---|---|
| SASEAGVRWGRPVGRRRRP | 19 | 19 ± 1 |
| TAQGA[Ac-K]AA[Dnp-K]-Ahx-r-r-r-NH2£ | 8£ | 32* |
| SASEAGV | 7 | 0.2 ± 0.1 |
| SASEAGVAEQVKKLSVNDS | 19 | 0.5 ± 0.1 |
| Lysine | 1 | 0.1 ± 0.1 |
| Arginine | 1 | 0.6 ± 0.1 |
| Serotonin | 1 | <0.02 |
| 5-Methoxytryptamine | 1 | 0.4 ± 0.1 |
| TQTF | 4 | 21 ± 0.5 |
| TQTFIP | 6 | 19 ± 0.4 |
| TQTFIPGK | 8 | 33 ± 0.9 |
| TQTFIPGKDA | 10 | 24 ± 0.9 |
| TQTFIPGKDAALEDS | 15 | 19 ± 0.6 |
| TQTFIPGKDAALEDSIARFQQK | 22 | 30 ± 1 |
| TQTFIPGSDAALEDSIASFQQS | 22 | 13 ± 1 |
| TQTFIPGKDARWGRPVGRRRRP | 22 | 757 ± 42 |
| AVAANKR | 7 | 1.4 ± 0.3 |
| AVAANKRSVM | 10 | 11 ± 0.3 |
| SNSYDSS | 7 | 5.2 ± 0.3 |
| SNSYDSSSIK | 10 | 9.9 ± 0.3 |
| MNMPMTERIR | 10 | 22 ± 1 |
| RTNPTTS | 7 | <0.02 |
| RTNPTTSNPE | 10 | <0.02 |
$
All values were measured with the PDH-coupled assay in the presence of 100 μM Ac-CoA and of His-MBP-GNAT2 fusion (1–20 μM).
£
Dnp is for di-nitro phenyl substitution on the ε-amino group, Ahx is an aminohexanoic spacer, and r is for D-Arg (see Seidel et al., 2016).
*
Data from Bienvenut et al. (2020), measured with Maltose Binding Protein (MBP)-AtGNAT2 fusion.