Table S1.
Crystallographic data and refinement statistics
| apo | GDPCP | GDP | ppGpp | |
| Data collection | ||||
| Cell parameters, Å | a = 242, | a = 237.5, | a = 242.0, | a = 244.3, |
| b = 242, | b = 237.5, | b = 242.0, | b = 244.3, | |
| c = 242, | c = 237.5 | c = 242.0 | c = 244.3 | |
| Space group | I41 | I4132 | I4132 | I4132 |
| Resolution range,* Å | 50.00–3.30 (3.51–3.30) | 48.49–3.66 (3.86–3.66) | 47.45–3.80 (4.00–3.80) | 47.91–4.00 (4.24–4.00) |
| Redundancy | 17.3 (15.1) | 18.4 (17.3) | 17.8 (17.8) | 18.2 (18.0) |
| Observed reflections >1σ | 601,153 | 236,914 | 189,332 | 196,017 |
| Unique reflections | 86,230 (5,081) | 12,870 (1,802) | 10,596 (1,654) | 10,792 (1,675) |
| Completeness, % | 96.1 (90.1) | 99.5 (97.2) | 99.6 (98.7) | 99.6 (99.2) |
| Overall (I/ σ (I)) | 17.1 (1.1) | 14.3 (2.1) | 14.96 (1.31) | 14 (0.82) |
| CC(1/2) | 99.9 (87.2) | 99.9 (79.2) | 99.9 (46.2) | 99.9 (60.2) |
| Rsym,† % | 18.9 (301.9) | 14.1 (145) | 17.2 (228) | 16.3 (386) |
| Refinement‡ | ||||
| Resolution range, Å | 49.4–3.3 | 48.49–3.7 | 47.45–3.80 | 47.91–4.00 |
| Rwork§ (no. of reflections) | 0.26 (85198) | 0.24 (11,598) | 0.25 (10,584) | 0.25 (9,974) |
| Rfree¶ (no. of reflections) | 0.28 (9,472) | 0.30 (940) | 0.31 (1,176) | 0.32 (809) |
| rmsd bond lengths, Å | 0.013 | 0.010 | 0.010 | 0.010 |
| rmsd bond angles, o | 1.34 | 1.70 | 1.52 | 1.44 |
| Average B factors, Å2 | ||||
| Main chain | 131.10 | 150.60 | 238.8 | 290 |
| Side chain | 140.00 | 157.80 | 246.4 | 297 |
*
The high-resolution bin details are in the parentheses.
†
Rsym = ∑|Ii – <I>|/|Ii| where Ii is the intensity of the ith measurement, and <I> is the mean intensity for that reflection.
‡
Reflections with I > σ was used in the refinement.
§
Rwork = |Fobs – Fcalc|/|Fobs|, where Fcalc and Fobs are the calculated and observed structure factor amplitudes, respectively.
¶
Rfree = as for Rwork, but for 5–10% of the total reflections chosen at random and omitted from refinement.