Table 2.
Comparison of kinetic constants for reactions catalyzed by DraT from R. rubrum or the DraT-GlnB complex from A. brasilense using A. vinelandii Fe protein as the acceptor
| Fe protein as the acceptor of ADP-ribose | Vmaxa | kcat (s−1)b | Km (μM)c | kcat/Km (s−1 M−1) | Reference |
|---|---|---|---|---|---|
| A. brasilense DraT-GlnB | 6.72 | 0.501 | 166 | 3,018.1 | This work |
| R. rubrum DraT | 0.072 | 0.0022 | 22 | 100 | 39 |
| 1.48 | 0.044 | 268 | 164.2 | 40 |
a
The values represent nmol of ADP-ribose transferred s−1 mg DraT−1 or nmol ADP-ribosylated Fe protein s−1 mg DraT-GlnB complex−1.
b
DraT was considered 30,000 Da and DraT-GlnB complex 74,504 Da (calculated based on the sequence using the Expasy program).
c
Km for NAD+ in the presence of Mg-ADP.