1JL4

CRYSTAL STRUCTURE OF THE HUMAN CD4 N-TERMINAL TWO DOMAIN FRAGMENT COMPLEXED TO A CLASS II MHC MOLECULE

Experimental procedure

Experimental method	SINGLE WAVELENGTH
Source type	SYNCHROTRON
Source details	APS BEAMLINE 19-ID
Synchrotron site	APS
Beamline	19-ID
Temperature [K]	100
Detector technology	CCD
Collection date	2000-12-12
Detector	SBC-2
Wavelength(s)	1.033
Spacegroup name	P 43 2 2
Unit cell lengths	145.195, 145.195, 103.846
Unit cell angles	90.00, 90.00, 90.00

Refinement procedure

Resolution	20.000 - 4.300
R-factor	0.428
Rwork	0.420
R-free	0.45300
Structure solution method	MOLECULAR REPLACEMENT
Starting model (for MR)	1IAK and 3CD4
Data reduction software	DENZO
Data scaling software	SCALEPACK
Phasing software	AMoRE
Refinement software	REFMAC

Data quality characteristics

	Overall	Outer shell
Low resolution limit [Å]	30.000	4.500
High resolution limit [Å]	4.300	4.300
Rmerge	0.152	0.610
Number of reflections	7428
<I/σ(I)>	12	2
Completeness [%]	83.0	56
Redundancy	9.6 *	7.8

Crystallization Conditions

crystal ID	method	pH	temperature	details
1	VAPOR DIFFUSION, HANGING DROP	8.5	297	17% PEG 4,000/0.2M Li2SO4/0.1M Tris, pH 8.5, VAPOR DIFFUSION, HANGING DROP, temperature 297K

Crystallization Reagents in Literatures

ID	crystal ID	solution	reagent name	concentration (unit)	details
1	1	drop	protein	20 (mg/ml)
2	1	reservoir	PEG4000	17 (%)
3	1	reservoir		0.2 (M)
4	1	reservoir	Tris	0.1 (M)