1K4T

HUMAN DNA TOPOISOMERASE I (70 KDA) IN COMPLEX WITH THE POISON TOPOTECAN AND COVALENT COMPLEX WITH A 22 BASE PAIR DNA DUPLEX

X-RAY DIFFRACTION

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Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, SITTING DROP	6.5	289	PEG 8000, Ammonium Sulfate, MES, pH 6.5, VAPOR DIFFUSION, SITTING DROP, temperature 289K

Crystal Properties
Matthews coefficient	Solvent content
2.96	58.43

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 57.093	α = 90
b = 116.26	β = 94.16
c = 75.217	γ = 90

Symmetry
Space Group	P 1 21 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				M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	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	2.1	20		0.062	18.6		46866	46866			18.1

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)
	2.1	2.15	32.8		0.325	1.71

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Resolution (High)	Resolution (Low)	Number Reflections (All)	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	2.1	19.89	45727	45727	4384	80.2	0.229	0.269	RANDOM	40.1

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]
-2.67		1.41	-1.96		4.62

RMS Deviations
Key	Refinement Restraint Deviation
c_dihedral_angle_d	21.1
c_improper_angle_d	3.59
c_angle_deg	1.2
c_bond_d	0.006
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
c_mcbond_it
c_mcangle_it
c_scbond_it
c_scangle_it

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	4687
Nucleic Acid Atoms	892
Solvent Atoms	227
Heterogen Atoms	77

Software

Software
Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
CNX	refinement
CNX	phasing