crystal structure of lactose synthase, a 1:1 complex between beta1,4-galactosyltransferase and alpha-lactalbumin in the presence of GlcNAc
X-RAY DIFFRACTION
Crystallization
| Crystalization Experiments | ||||
|---|---|---|---|---|
| ID | Method | pH | Temperature | Details |
| 1 | VAPOR DIFFUSION, HANGING DROP | 5.5 | 298 | sodium citrate, PEG 4000, pH 5.5, VAPOR DIFFUSION, HANGING DROP, temperature 298K |
| Crystal Properties | |
|---|---|
| Matthews coefficient | Solvent content |
| 2.67 | 53.6 |
Crystal Data
| Unit Cell | |
|---|---|
| Length ( Å ) | Angle ( ˚ ) |
| a = 57.161 | α = 90 |
| b = 96.379 | β = 100.98 |
| c = 99.48 | 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 | ADSC QUANTUM 4 | mirrors | 2000-08-09 | M | SINGLE WAVELENGTH | |||||
| Radiation Source | |||||
|---|---|---|---|---|---|
| ID # | Source | Type | Wavelength List | Synchrotron Site | Beamline |
| 1 | SYNCHROTRON | NSLS BEAMLINE X9B | 0.980 | NSLS | X9B |
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 | 2 | 25 | 94 | 0.07 | 12.5 | 2.2 | 68631 | 1 | 13.1 | ||||||||||
| 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 | 2 | 2.07 | 77 | 0.335 | 2.6 | 5621 | |||||||||||||
Refinement
| Statistics | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Diffraction ID | Structure Solution Method | Cross Validation method | Resolution (High) | Resolution (Low) | 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 | MOLECULAR REPLACEMENT | THROUGHOUT | 2 | 24.5 | 68053 | 6887 | 95.1 | 0.211 | 0.21 | 0.2037 | 0.258 | 0.2511 | RANDOM | 29.4 | |||||
| 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] | |
| 0.64 | 0.77 | 4.26 | -4.9 | |||
| RMS Deviations | |
|---|---|
| Key | Refinement Restraint Deviation |
| c_dihedral_angle_d | 24.6 |
| c_angle_deg | 1.7 |
| c_improper_angle_d | 1.03 |
| c_bond_d | 0.012 |
| c_bond_d_na | |
| c_bond_d_prot | |
| c_angle_d | |
| c_angle_d_na | |
| c_angle_d_prot | |
| c_angle_deg_na | |
| Non-Hydrogen Atoms Used in Refinement | |
|---|---|
| Non-Hydrogen Atoms | Number |
| Protein Atoms | 6396 |
| Nucleic Acid Atoms | |
| Solvent Atoms | 770 |
| Heterogen Atoms | 32 |
Software
| Software | |
|---|---|
| Software Name | Purpose |
| DENZO | data reduction |
| SCALEPACK | data scaling |
| AMoRE | phasing |
| CNS | refinement |














