4DST

Small-molecule ligands bind to a distinct pocket in Ras and inhibit SOS-mediated nucleotide exchange activity

Experimental procedure

Experimental method	SINGLE WAVELENGTH
Source type	SYNCHROTRON
Source details	ALS BEAMLINE 5.0.2
Synchrotron site	ALS
Beamline	5.0.2
Temperature [K]	93
Detector technology	CCD
Collection date	2010-09-03
Detector	ADSC QUANTUM 315
Wavelength(s)	0.97740
Spacegroup name	H 3
Unit cell lengths	78.923, 78.923, 78.631
Unit cell angles	90.00, 90.00, 120.00

Refinement procedure

Resolution	25.793 - 2.300
R-factor	0.1617
Rwork	0.159
R-free	0.20870
Structure solution method	MOLECULAR REPLACEMENT
RMSD bond length	0.005
RMSD bond angle	1.005
Data reduction software	HKL-2000
Data scaling software	SCALEPACK
Phasing software	PHASER
Refinement software	PHENIX ((phenix.refine: 1.6.4_486))

Data quality characteristics

	Overall	Outer shell
Low resolution limit [Å]	30.000	2.380
High resolution limit [Å]	2.300	2.300
Number of reflections	8242
<I/σ(I)>	18	3
Completeness [%]	94.5	70.8
Redundancy	5.2	3.3

Crystallization Conditions

crystal ID	method	pH	temperature	details
1	VAPOR DIFFUSION, SITTING DROP	8.5	277	0.2 uL + 0.2 uL drops containing 40 mg/mL KRas, 0.1 M TrisCl, 25% polyethylene glycol 4000, 0.2 M NaOAc, 2% benzamidine-HCl, pH 8.5, VAPOR DIFFUSION, SITTING DROP, temperature 277K