1QGU

NITROGENASE MO-FE PROTEIN FROM KLEBSIELLA PNEUMONIAE, DITHIONITE-REDUCED STATE

X-RAY DIFFRACTION

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Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	LIQUID DIFFUSION	8		CRYSTALLIZED ANAEROBICALLY USING LIQUID-LIQUID DIFFUSION TECHNIQUE. FINAL CONCENTRATIONS AFTER EQUILIBRATION WERE: 7% (W/V) PEG 6000, 0.4 - 0.6 M MGCL2, 50 MM TRIS-HCL PH 8, 3.3 MG/ML PROTEIN., pH 8.0 PRIOR TO DATA COLLECTION THE CRYSTAL WAS INCUBATED FOR 24 HOURS IN CRYOPROTECTANT (MOTHER LIQUOR WITH 25% ETHYLENE GLYCOL) CONTAINING 10 MM SODIUM DITHIONITE (A REDUCTANT).

Crystal Properties
Matthews coefficient	Solvent content
2.31	46

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 204.03	α = 90
b = 75.3	β = 122.61
c = 163.01	γ = 90

Symmetry
Space Group	C 1 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	IMAGE PLATE	MARRESEARCH	RH COATED SI MIRROR	1997-10-01	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	SRS BEAMLINE PX9.6		SRS	PX9.6

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	1.6	50	95.9	0.06	22.4	4.1		260359		-3	14.8

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)
	1.6	1.63	96.4		0.171	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-Work	R-Free	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	THROUGHOUT	1MIN	1.6	50	260359	13095	95.9	0.156	0.199	RANDOM	17.79

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]

RMS Deviations
Key	Refinement Restraint Deviation
p_transverse_tor	34.5
p_staggered_tor	13.3
p_planar_tor	5.2
p_scangle_it	3.715
p_scbond_it	3.033
p_mcangle_it	2.124
p_mcbond_it	1.701
p_multtor_nbd	0.261
p_singtor_nbd	0.169
p_chiral_restr	0.118
p_xyhbond_nbd	0.112
p_planar_d	0.034
p_angle_d	0.028
p_plane_restr	0.0273
p_bond_d	0.014
p_angle_deg
p_hb_or_metal_coord
p_xhyhbond_nbd
p_orthonormal_tor
p_special_tor

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	15528
Nucleic Acid Atoms
Solvent Atoms	2736
Heterogen Atoms	198

Software

Software
Software Name	Purpose
AMoRE	phasing
REFMAC	refinement
DENZO	data reduction
SCALEPACK	data scaling