For a counterexample, from Iwata's group,
Horsefield et al. Succinate: quinone oxidoreductase Acta. Cryst.(2003). D59,
600-602:
"It proved critical to freeze the crystals within 72 h of crystallization set-up. Crystals that were frozen after this time limit
showed no diffraction. This alteration in properties was apparent by the change in colour from deep orange to pale yellow that was
observed in crystals more than four weeks old (Fig. 1c). The deep orange colour of the crystals is attributed to the presence of
haem b within the protein. The loss or breakdown of haem, demonstrated by the change of colour in the crystals, could lead to
structural instability and consequently loss of diffraction. "
I've heard the Fe-S clusters of E. coli SDH are oxygen-sensitive in the
isolated enzyme.
The mitochondrial counterpart is more stable, we've collected data from
crystals 1-2 years old,
and seen "conversion" (new crystals grow while old crystals dissolve) to a new
space group
with better diffraction (that was a within few months after setup).
Edward Snell wrote:
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Dear All,
I was recently trying to find references on how age may degrade a
crystal, i.e. grow them and use them or preserve them as fresh as
possible. I seem to remember seeing a couple of papers on this but my
memory is fading and I have been unable to locate them. Can anyone jog
my memory or tell me if I'm imagining things? I've found plenty on the
protein prep etc. but nothing on the crystal.
Thanks,
Eddie.
Edward Snell Ph.D.
Assistant Prof. Department of Structural Biology, SUNY Buffalo,
Hauptman-Woodward Medical Research Institute
700 Ellicott Street, Buffalo, NY 14203-1102
Phone: (716) 898 8631 Fax: (716) 898 8660
Email: esn...@hwi.buffalo.edu Telepathy: 42.2 GHz
Heisenberg was probably here! Crystallization, how quaint!
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