TABLE I. FtsZ assembly rate constants in two different buffers.
Both buffers contain Mg2+, and they differ in pH. The rates from the present FRET assay are compared with those obtained previously for FtsZ-L68W. k1 and k-1 are the parameters for monomer activation, k2 and k-2 are for formation of the dimer nucleus, and ke and k-e are for elongation.
| Protein | Buffer | k1 | k-1 | k2 | ke | k-2 | k-e | k-2/k2 | k-e/ke |
|---|---|---|---|---|---|---|---|---|---|
| s-1 | s-1 | μM-1 s-1 | μM-1 s-1 | s-1 | s-1 | μM | μM | ||
| FtsZ-F268C | HMK | 0.38 | 0.01 | 0.72 | 6.63 | 199.6 | 4.0 | 277.2 | 0.60 |
| MMK | 0.38 | 0.01 | 0.79 | 6.60 | 199.8 | 3.48 | 252.9 | 0.53 | |
| FtsZ-L68W | HMK | 0.70 | 0.04 | 1.02 | 3.61 | 1.23 | 0.36 | 1.21 | 0.10 |
| MMK | 0.76 | 0.11 | 0.62 | 3.01 | 0.30 | 0.60 | 0.47 | 0.20 |