3CMU

Mechanism of homologous recombination from the RecA-ssDNA/dsDNA structures

X-RAY DIFFRACTION

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Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1		7.5		RecA6 fusion protein was incubated with a 3-fold molar excess of ssDNA (dT)18 in the original protein buffer supplemented with 2 mM ADP, 10 mM MgCl2 and 8 mM AlF4, pH 6.0. Crystals of the RecA6-(ADP-AlF4-Mg)6-(dT)18 complex were grown from 50 mM Hepes-Na+, 1.5% (w/v) polyethylene glycol (PEG) 3350, 4% (w/v) polyvinylpyrrolidone K15 (PVP K15), 25% (v/v) 2-methyl-2,4-pentandiol (MPD), 10 mM DTT, pH 7.5.

Crystal Properties
Matthews coefficient	Solvent content
3.3	62.76

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 156	α = 90
b = 156	β = 90
c = 211	γ = 120

Symmetry
Space Group	P 32 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					2006-10-01	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	APS BEAMLINE 24-ID-C		APS	24-ID-C

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (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	4.2	40					16125

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	R-Free	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	THROUGHOUT	4.2	12	16125	905	80.7	0.276	0.275	0.298	RANDOM	194.78

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]
15.22	7.61		15.22		-22.82

RMS Deviations
Key	Refinement Restraint Deviation
r_dihedral_angle_2_deg	35.914
r_dihedral_angle_3_deg	19.574
r_dihedral_angle_4_deg	15.676
r_dihedral_angle_1_deg	5.831
r_scangle_it	2.773
r_mcangle_it	1.96
r_scbond_it	1.577
r_angle_refined_deg	1.441
r_mcbond_it	1.089
r_symmetry_vdw_refined	0.426
r_symmetry_hbond_refined	0.372
r_nbtor_refined	0.312
r_nbd_refined	0.245
r_chiral_restr	0.158
r_xyhbond_nbd_refined	0.155
r_bond_refined_d	0.012
r_gen_planes_refined	0.004
r_bond_other_d
r_angle_other_deg
r_gen_planes_other
r_nbd_other
r_nbtor_other
r_xyhbond_nbd_other
r_metal_ion_refined
r_metal_ion_other
r_symmetry_vdw_other
r_symmetry_hbond_other
r_symmetry_metal_ion_refined
r_symmetry_metal_ion_other
r_mcbond_other
r_rigid_bond_restr
r_sphericity_free
r_sphericity_bonded

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	14598
Nucleic Acid Atoms	297
Solvent Atoms
Heterogen Atoms	198

Software

Software
Software Name	Purpose
REFMAC	refinement