4U13

Crystal structure of putative polyketide cyclase (protein SMa1630) from Sinorhizobium meliloti at 2.3 A resolution

Experimental procedure

Experimental method	SINGLE WAVELENGTH
Source type	SYNCHROTRON
Source details	APS BEAMLINE 21-ID-G
Synchrotron site	APS
Beamline	21-ID-G
Temperature [K]	100
Detector technology	CCD
Collection date	2013-11-11
Detector	MARMOSAIC 300 mm CCD
Wavelength(s)	0.97856
Spacegroup name	P 1 21 1
Unit cell lengths	47.764, 42.295, 62.287
Unit cell angles	90.00, 111.83, 90.00

Refinement procedure

Resolution	50.000 - 2.300
R-factor	0.1942
Rwork	0.193
R-free	0.22380
Structure solution method	MOLECULAR REPLACEMENT
Starting model (for MR)	3fh1
RMSD bond length	0.017
RMSD bond angle	1.689
Data reduction software	HKL-3000
Data scaling software	HKL-3000
Phasing software	HKL-3000
Refinement software	REFMAC (5.8.0073)

Data quality characteristics

	Overall	Inner shell	Outer shell
Low resolution limit [Å]	50.000	50.000	2.340
High resolution limit [Å]	2.300	6.240	2.300
Rmerge	0.070	0.049	0.674
Total number of observations	38669
Number of reflections	10379
<I/σ(I)>	12.9		2.1
Completeness [%]	99.3	98.6	92.5
Redundancy	3.7	3.3	3.2

Crystallization Conditions

crystal ID	method	pH	temperature	details
1	VAPOR DIFFUSION, SITTING DROP	7.5	289	0.2 ul of 18 mg/ml protein in 20 mM HEPES pH 7.5, 150 mM NaCl, 10% Glycerol, 0.1% Sodium Azide and 0.5 mM TCEP were mixed with 0.2 ul of the MCSG condition #96 (0.2 M Lithium Sulfate, 0.1 M HEPES:NaOH pH 7.5, 25% (w/v) PEG 3350) and equilibrated against 1.5 M NaCl solution in 96 Well 3 drop Crystallization Plate (Swissci). Before crystallization protein was incubated with 1/50 v/v of 2 mg/ml chymotrypsin solution at 289 K for 3 hours.