100 Years of X-ray Crystallography (IYCr2014)
1: Bird GH, Irimia A, Ofek G, Kwong PD, Wilson IA, Walensky LD. Stapled HIV-1
AND TRICKS -
Effect of PEG
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I had one case where PEG4000 grown crystals would be resistant to dissolving and would easily bend; the thinner rods would spring back staight. After placing the crystals into buffer known to dissolve them, I poked the crystals hard and the insides squeezed out like toothpaste, leaving an empty sack behind. the bottom-line is that fresh crystals diffracted better than old crystals because of this cross-linking.
Suggestions: (1) Make your PEG stocks up fresh or store them in the freezer as aliquots; (2) Remove oxidized PEGs from your stocks (See Ray et al. Biochemistry, 30, 6866-6875, 1991 and Jurnak, J. Cryst. Growth, 76, 577-582, 1986); (3) Check to see if freshly grown crystals behave better.
ARCHIVE: Introduction, Pre-crystallization, Crystallization, Post-crystallization, Derivatization, Cryoprotection, Diffraction, Symmetry, Structure Solution, Structure Refinement, Structure Analysis & Presentation.
for Refinement and Deposition/Publication
Xinhua Ji (NCI): Click and see my recent lab seminar at the Macromolecular Crystallography Laboratory (MCL) of the NCI for further discussion. Please let me know if you would like to discuss on this topic.
ARCHIVE: Test-set-and-R-free, Twinning, Low Resolution Crystallography, PHASER, HKL2000, Parallel Expression, Structural Genomics, NCS, Missing Atoms, Trends in Crystallography, Absorption Correction, Data for Refinement and Publication.
AND TUTORIALS NEW ADDITION - Structure Factor
RCAKU WEBINAR SERIES (2009 - PRESENT)
LOW RESOLUTION PHASING AND REFINEMENT (2011)
CRYSTALLOGRAPHY: SEEING THINGS IN A DIFFERENT LIGHT (2013)
CRYSTALLOGRAPHY: FOR ASPIRING CRYSTALLOGRAPHERS (2013)
STRUCTURE FACTOR TUTORIAL BY KEVIN COWTAN (2014)
- NEW ADDITION - Protein Geometry
Databases: BMCD, CryoD, DisProt, ExPASy, HAD, HIC-Up, Metal Sites, NDB, PDB, PDBe,
Protein Geometry Database, Scattering
Programs: CCP4, COOT, DSSR, HKL, PHENIX, PyMOL, SOLVE, USF, XDS
Servers: Anisotropy, CheckMyMetal, Crystal, C6, Dali, DSSR, ESPript, Grade,
PDBePISA, Phyre, Probity, Protein, Robetta Fragment & HHpred,
Facilities: APS SER-CAT, APS SAXS Capabilities
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