8FIL

Zinc-free APOBEC3A (inactive E72A mutant) in complex with TTC-hairpin DNA substrate

Experimental procedure

Experimental method	SINGLE WAVELENGTH
Source type	SYNCHROTRON
Source details	AUSTRALIAN SYNCHROTRON BEAMLINE MX2
Synchrotron site	Australian Synchrotron
Beamline	MX2
Temperature [K]	100
Detector technology	PIXEL
Collection date	2022-09-28
Detector	DECTRIS EIGER X 16M
Wavelength(s)	0.953739
Spacegroup name	P 1 21 1
Unit cell lengths	54.750, 57.352, 93.739
Unit cell angles	90.00, 105.78, 90.00

Refinement procedure

Resolution	40.940 - 2.010
R-factor	0.23292
Rwork	0.231
R-free	0.26586
Structure solution method	MOLECULAR REPLACEMENT
Starting model (for MR)	5keg
RMSD bond length	0.008
RMSD bond angle	1.976
Data reduction software	XDS
Data scaling software	Aimless
Phasing software	MOLREP
Refinement software	REFMAC (5.8.0267)

Data quality characteristics

	Overall	Outer shell
Low resolution limit [Å]	48.400	2.150
High resolution limit [Å]	2.010	2.010
Rmerge	0.113	1.294
Rpim	0.081	0.955
Number of reflections	36510	2435
<I/σ(I)>	6.1	0.7
Completeness [%]	97.8	88.3
Redundancy	2.8	2.6
CC(1/2)	0.992	0.188

Crystallization Conditions

crystal ID	method	pH	temperature	details
1	VAPOR DIFFUSION, HANGING DROP	6.6	285	A3A-E72A (50 mM MES pH 6.0, 100 mM NaCl, 1 mM TCEP, 0.2 mM EDTA) was mixed with oligonucleotides (10 mM Tris/HCl pH 7.9, 1 mM EDTA) at 0.85 mM and 1.7 mM respectively. Dilution was done with protein buffer. The mixture was added to crystallization liquid 1 to 1 and the mixture was pipetted on siliconized glass disks and sealed on top of a reservoir of crystallization liquid for hanging drop crystallization at 12 degrees Celsius. The crystallization liquid has the following composition: 100 mM Bicine at pH 6.6, 200 mM NaCl, 20 mM putrescine, 1 mM TCEP, 1 mM inositol hexaphosphate (phytic acid) and 45 % pentaerythritol propoxylate (5/4 PO/OH)