1V16

CROSSTALK BETWEEN COFACTOR BINDING AND THE PHOSPHORYLATION LOOP CONFORMATION IN THE BCKD MACHINE

X-RAY DIFFRACTION

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Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	1OLS	PDB ENTRY 1OLS

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION	5.5	293	CRYSTALS WERE GROWN AT 20C VIA THE VAPOR DIFFUSION METHOD BY MIXING EQUAL AMOUNTS OF PROTEIN (20-25 MG/ML IN 50 MM HEPES/NAOH, PH 7.5, 250 MM KCL, 0.5 MM PMSF, 1 MM BENZAMIDINE AND 5% (V/V) GLYCEROL) WITH WELL SOLUTION (1.4-1.6 M AMMONIUM SULFATE, 0.1 M NA-CITRATE PH 5.8, 20 MM B-MERCAPTOETHANOL). SERIALLY DILUTED CRUSHED CRYSTALS WERE USED FOR MICRO-SEEDING ONE DAY AFTER THE DROPS WERE SET UP. CRYSTALS APPEARED ONE DAY AFTER SEEDING AND GREW TO A MAXIMUM SIZE OF 120 X 800 UM WITHIN 10 DAYS. CRYSTALS WERE STABILIZED FOR 12 HOURS BY TRANSFER TO FRESH WELL SOLUTION. THEY WERE THEN CRYO-PROTECTED BY STEP-WISE TRANSFER INTO CRYO-BUFFER CONTAINING 1.6 M AMMONIUM SULFATE, 50 MM HEPES, PH 7.5, 100 MM NA-CITRATE, PH 5.8, 100 MM KCL, 50 MM DTT AND UP TO 20% (V/V) GLYCEROL. IT WAS FOUND THAT MN2+ IONS COULD REPLACE THE MG2+ REQUIRED FOR THE BINDING OF THDP TO THE ENZYME.

Crystal Properties
Matthews coefficient	Solvent content
2.5	53.4

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 145.397	α = 90
b = 145.397	β = 90
c = 69.104	γ = 120

Symmetry
Space Group	P 31 2 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			2003-07-25	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	APS BEAMLINE 19-ID		APS	19-ID

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (Observed)	R Merge 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	1.9	35.87	99.3	0.091	20.4	5.9		65864		-3

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	R Merge I (Observed)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
1	1.9	1.93	100		0.635	3.2	5.8

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Starting model	Resolution (High)	Resolution (Low)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Factor (Observed)	R-Work	R-Free	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	THROUGHOUT	PDB ENTRY 1OLS	1.9	33.33	64317	1540	99.3	0.132	0.131	0.17	RANDOM	15.28

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]
-0.01	-0.01		-0.01		0.02

RMS Deviations
Key	Refinement Restraint Deviation
r_dihedral_angle_1_deg	6.074
r_scangle_it	4.783
r_scbond_it	2.902
r_mcangle_it	1.772
r_angle_refined_deg	1.638
r_mcbond_it	0.978
r_angle_other_deg	0.928
r_symmetry_vdw_other	0.297
r_nbd_other	0.248
r_nbd_refined	0.216
r_symmetry_hbond_refined	0.196
r_xyhbond_nbd_refined	0.175
r_symmetry_vdw_refined	0.172
r_chiral_restr	0.116
r_metal_ion_refined	0.103
r_nbtor_other	0.086
r_bond_refined_d	0.02
r_gen_planes_other	0.011
r_gen_planes_refined	0.01
r_bond_other_d	0.002
r_dihedral_angle_2_deg
r_dihedral_angle_3_deg
r_dihedral_angle_4_deg
r_nbtor_refined
r_xyhbond_nbd_other
r_metal_ion_other
r_symmetry_hbond_other
r_symmetry_metal_ion_refined
r_symmetry_metal_ion_other
r_mcbond_other
r_mcangle_other
r_scbond_other
r_scangle_other
r_long_range_B_refined
r_long_range_B_other
r_rigid_bond_restr
r_sphericity_free
r_sphericity_bonded

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	5596
Nucleic Acid Atoms
Solvent Atoms	571
Heterogen Atoms	60

Software

Software
Software Name	Purpose
REFMAC	refinement
HKL-2000	data reduction
HKL-2000	data scaling