data for structural and crystallization communications - example

Example 1: hanging-drop vapour diffusion

Crystallization 1: All crystallization experiments were performed using the hanging-drop vapour diffusion method at ambient temperature. Initial crystallization conditions for Xase were identified from the PEG/Ion Screen (Hampton Research). Crystals suitable for X-ray diffraction analysis (typical dimensions are 0.05 x 0.03 x 0.02 mm3; Fig. 1) were grown from 1 μL drops containing equal volumes of protein (1.2 mg mL-1 in 50 mM Tris pH 7.5, 100 mM sodium chloride) and reservoir solution (25% PEG 3350, 100 mM Hepes pH 7.3, 200 mM diammonium citrate). Drops were equilibrated against 0.5 mL reservoir solution in the wells.
Cryo-conditions for crystal 1: Crystals were soaked in reservoir solution supplemented with 20% glycerol for 1-2 minutes prior to flash cooling by direct immersion into liquid nitrogen. The mounted crystal was subjected to two annealing treatments consisting of interruption of the flow of the cold stream with a plastic ruler for 10 seconds.
_exptl_crystal.crystal_id        1
_exptl_crystal.size_max          0.05
_exptl_crystal.size_mid          0.03
_exptl_crystal.size_min          0.02

_exptl_crystal_grow.crystal_id   1
_exptl_crystal_grow.method       'hanging-drop vapour diffusion'
_exptl_crystal_grow.temp_details 'ambient'

loop_
_pdbx_exptl_crystal_grow_sol.crystal_id  
_pdbx_exptl_crystal_grow_sol.sol_id      
_pdbx_exptl_crystal_grow_sol.volume
_pdbx_exptl_crystal_grow_sol.volume_units
_pdbx_exptl_crystal_grow_sol.pH

1    'protein'      0.5    'microlitre'    7.5
1    'precipitant'  0.5    'microlitre'    7.3
1    'reservoir'    0.5    'millilitre'    7.3

loop_
_pdbx_exptl_crystal_grow_comp.crystal_id
_pdbx_exptl_crystal_grow_comp.sol_id
_pdbx_exptl_crystal_grow_comp.comp_id
_pdbx_exptl_crystal_grow_comp.comp_name
_pdbx_exptl_crystal_grow_comp.conc
_pdbx_exptl_crystal_grow_comp.conc_units

1  'protein'      1  'protein'              1.2   'milligrams_per_millilitre'
1  'protein'      2  'Tris'                 50.   'millimolar'
1  'protein'      3  'NaCl'                 100.  'millimolar'

1  'reservoir'    1  'PEG 3350'             25.   'percent_weight_by_volume'
1  'reservoir'    2  'Hepes'                100.  'millimolar'
1  'reservoir'    3  'diammonium citrate'   200.  'millimolar'

1  'precipitant'  1  'PEG 3350'             25.   'percent_weight_by_volume'
1  'precipitant'  2  'Hepes'                100.  'millimolar'
1  'precipitant'  3  'diammonium citrate'   200.  'millimolar'

_pdbx_exptl_crystal_cryo_treatment.crystal_id     1

_pdbx_exptl_crystal_cryo_treatment.final_solution_details
; Crystals were soaked in reservoir solution supplemented with 20% glycerol
;
_pdbx_exptl_crystal_cryo_treatment.soak_details
;  1-2 min before flash-cooling 
;

_pdbx_exptl_crystal_cryo_treatment.cooling_details
;  direct immersion in liquid nitrogen
;

_pdbx_exptl_crystal_cryo_treatment.annealing_details
;  10 s interruption of cold stream with plastic ruler; performed twice
;

How this example will appear in the journal

Crystallization
Crystallization method Hanging-drop vapour diffusion  
Temperature Ambient
Crystallization solutions
   Protein (0.5 μl) Protein 1.2 mg ml-1, Tris 50 mM, NaCl 100 mM, pH 7.5
   Precipitant (0.5 μl) PEG 3350 25%(w/v), Hepes 100 mM, diammonium citrate 200 mM, pH 7.3
   Reservoir (0.5 ml) PEG 3350 25% (w/v), Hepes 100 mM, diammonium citrate 100 mM, pH 7.3
Cryo treatment
  Final cryoprotection solution Crystals were soaked in reservoir solution supplemented with 20% glycerol
  Soaking 1-2 min before flash-cooling
  Cooling Direct immersion in liquid nitrogen  
  Annealing 10 s interruption of cold stream with plastic ruler; performed twice  
 
Crystal data
Crystal size (mm) 0.05 × 0.03 × 0.02  



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