4ABA

Fragments bound to bovine trypsin for the SAMPL challenge

Experimental procedure

Experimental method	SINGLE WAVELENGTH
Source type	SYNCHROTRON
Source details	AUSTRALIAN SYNCHROTRON BEAMLINE MX1
Synchrotron site	Australian Synchrotron
Beamline	MX1
Temperature [K]	100
Detector technology	CCD
Collection date	2009-12-04
Detector	ADSC CCD
Spacegroup name	P 21 21 21
Unit cell lengths	54.513, 58.474, 66.693
Unit cell angles	90.00, 90.00, 90.00

Refinement procedure

Resolution	66.690 - 1.250
R-factor	0.14283
Rwork	0.142
R-free	0.16104
Structure solution method	MOLECULAR REPLACEMENT
Starting model (for MR)	1k1m
RMSD bond length	0.026
RMSD bond angle	2.520
Data reduction software	XDS
Data scaling software	SCALA
Phasing software	PHASER
Refinement software	REFMAC (5.6.0117)

Data quality characteristics

	Overall	Outer shell
Low resolution limit [Å]	44.000	1.320
High resolution limit [Å]	1.250	1.250
Rmerge	0.050	0.260
Number of reflections	56922
<I/σ(I)>	24.9	7.8
Completeness [%]	95.7	88.1
Redundancy	7.4	7.2

Crystallization Conditions

crystal ID	method	pH	temperature	details
1		5.8		22.5% PEG 3350, 0.18 M AMMONIUM SULFATE, 0.12 M SODIUM THIOCYANATE, 0.09 M BIS-TRIS PH 5.5, 0.01 M TRIS PH 8.5 (FINAL MEASURED PH=5.82). THE PROTEIN WAS AT 2 MM (47 MG/ML), WITH 4 MM BENZYLAMINE AND 10 MM CALCIUM CHLORIDE ADDED TO STABILIZE IT. THE CRYSTALLIZATIONS WERE SET UP WITH A PHOENITO PROTOCOL (NEWMAN ET AL. 2008), WHERE A PHOENIX ROBOT (ART ROBBINS INSTRUMENTS, SUNNYSIDE, CA) WAS USED TO DISPENSE THE PROTEIN INTO AN SD2 CRYSTALLIZATION PLATE (PRE-FILLED WITH 50 ML RESERVOIR SOLUTION) AND A MOSQUITO ROBOT (TTP LABTECH, MELBOURN, UK) WAS USED TO DISPENSE THE RESERVOIR SOLUTION AND SEED STOCK OVER THE PROTEIN DROPLET.