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<div><font face="Times" size="+2" color="#000000">One small comment
concerning negative-stain versus cryo-EM of frozen-hydrated specimens.
One of the best advantages of cryo-EM is that it preserves the aqueous
environment of the specimen, not only water, but also pH or
ionic-strength. This is not the case with negative stain and the
overall conformation of the macromolecular assemblies can be
drastically modified by these environmental changes. If the only goal
of three-dimensional reconstruction is to get "a" structure,
then negative-staining is probably fine. However, if you want to
interpret your structure in terms of its function, then cryo-EM is -
to my opinion- the only way to go.</font></div>
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<div><font color="#FF0000">_____________________________________<br>
Denis Chretien<br>
Equipe "Structure et Dynamique du Cytosquelette"<br>
UMR 6026 "Interactions Cellulaires et Moleculaires"<br>
Universite de Rennes 1<br>
Campus de Beaulieu, Bt 13<br>
35042 RENNES Cedex<br>
FRANCE<br>
_____________________________________<br>
tel: +33 (0) 2 23 23 67 64<br>
+33 (0) 6 62 00 84 57<br>
fax: +33 (0) 2 23 23 50 48<br>
email: denis.chretien@univ-rennes1.fr</font></div>
<div><font color="#FF0000">http://www.sdc.univ-rennes1.fr/<br>
_____________________________________</font></div>
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