Structure of the substrate-free form of the rebeccamycin biosynthetic enzyme REBC
X-RAY DIFFRACTION
Crystallization
| Crystalization Experiments | ||||
|---|---|---|---|---|
| ID | Method | pH | Temperature | Details |
| 1 | 7.4 | 298 | 1.5 microliters of RebC (9 mg/mL in 150 mM NaCl, 10% glycerol, 25 mM HEPES pH 7.5) were incubated with 0.35 microliters of guanidine-HCl for 30 seconds, followed by addition of 1.5 microliters of precipitant solution (19% PEG-8000, 0.1 M HEPES pH 7.4), without mixing, at room temperature and sealed over a precipitant well solution. Immediately after set up, crystal trays were placed on a gel shaker and then, after 12 hours, transferred to a storage space in vibration-isolation. Before being flash-frozen in liquid nitrogen, a crystal was soaked for five seconds in cryogenic solution (19% PEG-8000, 0.1 M HEPES pH 7.4, 20% glycerol), VAPOR DIFFUSION, HANGING DROP, temperature 298K, pH 7.40 | |
| Crystal Properties | |
|---|---|
| Matthews coefficient | Solvent content |
| 2.52 | 51.11 |
Crystal Data
| Unit Cell | |
|---|---|
| Length ( Å ) | Angle ( ˚ ) |
| a = 63.22 | α = 90 |
| b = 77.562 | β = 108.04 |
| c = 64.673 | γ = 90 |
| Symmetry | |
|---|---|
| Space Group | P 1 21 1 |
Diffraction
| Diffraction Experiment | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID # | Crystal ID | Scattering Type | Data Collection Temperature | Detector | Detector Type | Details | Collection Date | Monochromator | Protocol | |||||
| 1 | 1 | x-ray | 100 | CCD | MARMOSAIC 325 mm CCD | FLAT COLLIMATING MIRROR, DOUBLE CRYSTAL MONOCHROMATOR, TOROID FOCUSING MIRROR | 2006-07-09 | M | MAD | |||||
| Radiation Source | |||||
|---|---|---|---|---|---|
| ID # | Source | Type | Wavelength List | Synchrotron Site | Beamline |
| 1 | SYNCHROTRON | SSRL BEAMLINE BL9-2 | 1.8455, 1.8447, 0.9798 | SSRL | BL9-2 |
Data Collection
| Overall | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID # | Resolution (High) | Resolution (Low) | Percent Possible (Observed) | R Sym I (Observed) | Net I Over Average Sigma (I) | Redundancy | Number Reflections (All) | Number Reflections (Observed) | Observed Criterion Sigma (F) | Observed Criterion Sigma (I) | B (Isotropic) From Wilson Plot | ||||||||
| 1 | 1.8 | 50 | 93.9 | 0.09 | 25.4 | 7.2 | 52005 | ||||||||||||
| Highest Resolution Shell | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID # | Resolution (High) | Resolution (Low) | Percent Possible (All) | Percent Possible (Observed) | R-Sym I (Observed) | Mean I Over Sigma (Observed) | Redundancy | Number Unique Reflections (All) | |||||||||||
| 1.8 | 1.86 | 67.2 | 0.458 | 2.6 | |||||||||||||||
Refinement
| Statistics | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Diffraction ID | Structure Solution Method | Cross Validation method | Resolution (High) | Resolution (Low) | Number Reflections (All) | Number Reflections (Observed) | Number Reflections (R-Free) | Percent Reflections (Observed) | R-Factor (Observed) | R-Work (Depositor) | R-Work (DCC) | R-Free (Depositor) | R-Free (DCC) | R-Free Selection Details | Mean Isotropic B | ||||
| X-RAY DIFFRACTION | MAD | THROUGHOUT | 1.8 | 50 | 55046 | 51814 | 2566 | 94.1 | 0.211 | 0.211 | 0.21 | 0.241 | 0.23 | RANDOM | 41.7 | ||||
| Temperature Factor Modeling | ||||||
|---|---|---|---|---|---|---|
| Anisotropic B[1][1] | Anisotropic B[1][2] | Anisotropic B[1][3] | Anisotropic B[2][2] | Anisotropic B[2][3] | Anisotropic B[3][3] | |
| 4.011 | 5.453 | -15.012 | 11.001 | |||
| RMS Deviations | |
|---|---|
| Key | Refinement Restraint Deviation |
| c_scangle_it | 2.877 |
| c_mcangle_it | 2.194 |
| c_scbond_it | 1.976 |
| c_mcbond_it | 1.447 |
| c_angle_deg | 1.28 |
| c_bond_d | 0.006 |
| c_bond_d_na | |
| c_bond_d_prot | |
| c_angle_d | |
| c_angle_d_na | |
| Non-Hydrogen Atoms Used in Refinement | |
|---|---|
| Non-Hydrogen Atoms | Number |
| Protein Atoms | 3898 |
| Nucleic Acid Atoms | |
| Solvent Atoms | 427 |
| Heterogen Atoms | 54 |
Software
| Software | |
|---|---|
| Software Name | Purpose |
| HKL-2000 | data collection |
| SHARP | phasing |
| CNS | refinement |
| HKL-2000 | data reduction |
| SCALEPACK | data scaling |














