Table 1.
Sequences of active PurN heterodimers
| Number | N-terminal fragment | C-terminal fragment | Relative doubling time* |
|---|---|---|---|
| A46 | 1–72NQ | MLGS63–212 | 1.2 ± 0.1 |
| A36 | 1–65 | MLGS63–212 | 1.3 |
| A37 | 1–69VTS | MGS63–212 | 1.3 |
| A43 | 1–62 | MGS63–212 | 1.3 |
| A47 | 1–80GVAR | M63–212 | 1.3 |
| A42 | 1–62 | MGS63–212 | 1.4 ± 0.2 |
| A35 | 1–74 | M63–212 | 1.4 |
| A38 | 1–66LTS | MLGF63–212 | 1.4 |
| A39 | 1–72QRS | MLGS63–212 | 1.5 |
| A44 | 1–61 | MLGS63–212 | 1.5 |
| A34 | 1–63LTS | M63–212 | 1.5 |
| B31 | 1–113 | M112–112 | 1.2 |
| B15 | 1–114LTS | M114–212 | 1.2 |
| B30 | 1–112LTS | M109–212 | 1.3 |
| B13 | 1–111 | M114–212 | 1.4 ± 0.3 |
| B18 | 1–111 | M107–212 | 1.6 |
| B28 | 1–118TS | M112–212 | 2.7 |
| B27 | 1–112A | M112–212 | 5.7 |
| B17 | 1–112RS | M114–212 | 6.1 |
| WT control | 1–212 | 0.98 ± 0.06 | |
| WT control | 1–212 | 1.0 ± 0.02 |
The amino acid sequences were determined from the DNA sequence of the purN gene fragments. Because proteolytic processing of the fragments may occur (e.g. to shorten overlapping sequences), the exact amino acid sequence of active PurN heterodimers may differ.
*
The growth rate in minimal media of auxotrophic strain TX680F′ expressing the heterodimers was determined (see Materials and Methods). The doubling time during exponential growth is expressed relative to that of TX680F′ cells expressing the wild-type monomer from phagemid pDIM-C6. TX680F′ bearing control plasmids without any purN gene or with only one gene fragment showed no growth.