1RR8

Structural Mechanisms of Camptothecin Resistance by Mutations in Human Topoisomerase I

X-RAY DIFFRACTION

Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	1K4T	PDB ENTRY 1K4T

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, HANGING DROP	6.5	289	PEG 8000, 200mM Lithium Sulfate, 100mM Mes, pH 6.5, VAPOR DIFFUSION, HANGING DROP, temperature 289K

Crystal Properties
Matthews coefficient	Solvent content
3.07	59.99

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 57.59	α = 90
b = 115.585	β = 96.29
c = 75.01	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	MARRESEARCH		2002-02-04	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	NSLS BEAMLINE X25	1.1	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	2.6	20.02	92.9	0.085			30063	27855			35.9

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
	2.6	2.76	81.8

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Starting model	Resolution (High)	Resolution (Low)	Number Reflections (All)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Factor (All)	R-Factor (Observed)	R-Work	R-Free	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	THROUGHOUT	PDB ENTRY 1K4T	2.6	19.7	27855	27855	2744	10	0.242	0.292	0.242	0.294	RANDOM

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]
1.53		5.78	-7.52		5.99

RMS Deviations
Key	Refinement Restraint Deviation
c_dihedral_angle_d	22.6
c_angle_deg	2.2
c_improper_angle_d	1.55
c_bond_d	0.054

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	4124
Nucleic Acid Atoms	895
Solvent Atoms	304
Heterogen Atoms	63

Software

Software
Software Name	Purpose
HKL-2000	data collection
TRUNCATE	data reduction
AMoRE	phasing
CNS	refinement
HKL-2000	data reduction
CCP4	data scaling

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM157729.