8Q5W

MgADP-bound Fe protein of the molybdenum nitrogenase from Methanocaldococcus infernus

Experimental procedure

Experimental method	SINGLE WAVELENGTH
Source type	SYNCHROTRON
Source details	SLS BEAMLINE X06SA
Synchrotron site	SLS
Beamline	X06SA
Temperature [K]	100
Detector technology	PIXEL
Collection date	2022-09-03
Detector	DECTRIS EIGER X 16M
Wavelength(s)	0.99999
Spacegroup name	P 21 21 21
Unit cell lengths	147.948, 156.729, 206.454
Unit cell angles	90.00, 90.00, 90.00

Refinement procedure

Resolution	49.260 - 2.490
R-factor	0.222
Rwork	0.221
R-free	0.24200
Structure solution method	MOLECULAR REPLACEMENT
RMSD bond length	0.009
RMSD bond angle	1.258
Data reduction software	autoPROC
Data scaling software	autoPROC
Phasing software	PHENIX
Refinement software	PHENIX ((1.20.1_4487: ???))

Data quality characteristics

	Overall	Outer shell
Low resolution limit [Å]	120.260	2.830
High resolution limit [Å]	2.490	2.490
Rmerge	0.176	2.314
Rmeas	0.180	2.375
Rpim	0.040	0.529
Number of reflections	91224	4487
<I/σ(I)>	15.5	2
Completeness [%]	91.2	77.5
Redundancy	20.8	19.3
CC(1/2)	0.998	0.680

Crystallization Conditions

crystal ID	method	pH	temperature	details
1	VAPOR DIFFUSION, SITTING DROP	8.5	293.15	The purified protein was crystallised at a final concentration of 18.3 mg/ml with 2 mM ADP and 2 mM MgCl2 by spotting 0.7 ul of crystallisation solution with 0.7 ul of protein sample. Crystallisation was done anaerobically in a Coy tent containing N2/H2 (97:3%) atmosphere. The screening was done at 20 degrees Celsius on 96-Well MRC 2-drop polystyrene (SWISSCI) plates containing 90 ul of crystallisation solution. The crystallisation solution in which crystals were obtained contained 20 % w/v polyethylene glycol 3350, 100 mM Bis-Tris propane pH 8.5 and 200 mM sodium nitrate. Sealed plates were stored inside the same anaerobic chamber where the crystallisation was performed. The crystals in complex with MgADP were soaked in the crystallisation solution supplemented with 20% ethylene glycol prior to freezing in liquid nitrogen.