1A04

THE STRUCTURE OF THE NITRATE/NITRITE RESPONSE REGULATOR PROTEIN NARL IN THE MONOCLINIC C2 CRYSTAL FORM

Experimental procedure

Source type	ROTATING ANODE
Source details	RIGAKU
Temperature [K]	93
Detector technology	IMAGE PLATE
Collection date	1995-07-27
Detector	RIGAKU
Spacegroup name	C 1 2 1
Unit cell lengths	156.306, 38.527, 106.892
Unit cell angles	90.00, 131.91, 90.00

Refinement procedure

Resolution	8.000 - 2.200
R-factor	0.211
Rwork	0.211
R-free	0.26700
Structure solution method	MOLECULAR REPLACEMENT
Starting model (for MR)	1rnl
RMSD bond length	0.009
RMSD bond angle	1.360
Data reduction software	DENZO
Data scaling software	SCALEPACK
Phasing software	X-PLOR (3.1)
Refinement software	X-PLOR (3.1)

Data quality characteristics

	Overall	Outer shell
Low resolution limit [Å]	65.000	2.440
High resolution limit [Å]	2.200	2.200
Rmerge	0.078
Number of reflections	22871
<I/σ(I)>	9.8
Completeness [%]	99.9	99.3
Redundancy	5.4

Crystallization Conditions

crystal ID	method	pH	temperature	details
1	VAPOR DIFFUSION, SITTING DROP	7.6	4 *	THE PROTEIN SOLUTION CONTAINING 23.3 MG/ML OF PURIFIED NARL, 20 MM TRIS.HCL (PH=7.6), 0.5 MM MGCL2, AND 10% GLYCEROL WAS MIXED WITH AN EQUAL VOLUME OF THE RESERVOIR SOLUTION CONTAINING 0.1 M TRIS.HCL (PH=8.5), 0.2 M SODIUM ACETATE, AND 30% POLYETHYLENE GLYCOL (PEG) 4000. SITTING DROPS CONTAINING 20 ML OF MIXTURE WERE EQUILIBRATED BY VAPOR DIFFUSION AT 4 DEGREES AGAINST 20 ML OF THE RESERVOIR SOLUTION. CRYSTALS BEGAN TO APPEAR AS CLUSTERS OF PLATES AFTER 11-15 DAYS., vapor diffusion - sitting drop, temperature 277K

Crystallization Reagents in Literatures

ID	crystal ID	solution	reagent name	concentration (unit)	details
1	1	drop	NarL	11.65 (mg/ml)
10	1	reservoir	PEG4000	30 (%)
2	1	drop	Tris-HCl	10 (mM)
3	1	drop		0.25 (mM)
4	1	drop	glycerol	5 (%)
5	1	drop	Tris-HCl	0.05 (M)
6	1	drop	sodium acetate	0.1 (M)
7	1	drop	PEG4000	15 (%)
8	1	reservoir	Tris-HCl	0.1 (M)
9	1	reservoir	sodium acetate	0.2 (M)