Tips and Tricks in Crystallography

Dr. Xinhua Ji (NCI): Before Making SeMet-labeled Macromolecules, try quick soak with either halides (Dauter & Dauter, 1999, J Mol Biol 289:93-101; Dauter et al., 2001, Acta Crystallogr. D 57:239-249) or metals (Sun & Radaev, 2002, Acta Crystallogr. D 58:1099-1103; Sun et al., 2002, Acta Crystallogr. D 58:1092-1098). The beauty of quick soak is fast. In addition, the binding of metal atoms can be screened with mass spectrometry (Sun & Hammer, 2000, Acta Crystallogr D 56:161-168). Below are the main features of both quick-soak approaches. Dr. Zbigniew Dauter and Dr. Peter Sun are among us and are always ready to help.


Metal Quick Soak

Halide Quick Soak


~10 mM

~1 M


10 min 2 h

< 1 min

Binding Sites



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