2IBM

A novel dimer interface and conformational changes revealed by an X-ray structure of B. subtilis SecA

X-RAY DIFFRACTION

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Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	1M6N	pdb entry 1m6n

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, SITTING DROP	6.8	301	1.8 M malonate, pH 6.8, VAPOR DIFFUSION, SITTING DROP, temperature 301K

Crystal Properties
Matthews coefficient	Solvent content
3.13	60.67

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 125.834	α = 90
b = 166.833	β = 90
c = 211.99	γ = 90

Symmetry
Space Group	I 21 21 21

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	SBC-2	mirrors	2005-05-01	M	SINGLE WAVELENGTH
2	1	x-ray						M
1,2	1

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	APS BEAMLINE 19-ID		APS	19-ID
2	SYNCHROTRON	NSLS BEAMLINE X25		NSLS	X25

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	3.2	100	92.7	0.066	5.8	4.5		39088	7	2.7

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	3.2		92.7		0.571	2.7	4.4

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 1m6n	3.2	40.53	34442	3431	92.7	0.321	0.321	0.323	RANDOM	47.3

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]
-2.18			4.57		-2.39

RMS Deviations
Key	Refinement Restraint Deviation
c_dihedral_angle_d	24.3
c_mcangle_it	4.21
c_mcbond_it	2.65
c_improper_angle_d	2.09
c_scangle_it	1.97
c_angle_deg	1.8
c_scbond_it	1.36
c_bond_d	0.013
c_bond_d_na
c_bond_d_prot
c_angle_d
c_angle_d_na
c_angle_d_prot
c_angle_deg_na
c_angle_deg_prot
c_dihedral_angle_d_na
c_dihedral_angle_d_prot
c_improper_angle_d_na
c_improper_angle_d_prot

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	12376
Nucleic Acid Atoms
Solvent Atoms
Heterogen Atoms	27

Software

Software
Software Name	Purpose
CNS	refinement
HKL-2000	data collection
DENZO	data reduction
SCALEPACK	data scaling
PHASER	phasing