[3dem] virus aggregation in cryo-EM

[Juha Huiskonen]

Dear All,

I am studying a membrane virus (Uukuniemi Bunyavirus), which tends to
aggregate heavily, especially at acidic pH. We purify the virus
particles by pelleting the prep through an OptiPrep cushion and
resuspend the pellet in 10 mM Tris with 100 mM NaCl.

I would be happy to hear any suggestions on how to reduce (virus)
particle aggregation. Of course, what works in the end will be highly
dependent on each sample. But what would be sensible things to try in
your experience?

Fixation of particles with 0.1 % glutaraldehyde prior to pelleting
reduces aggregation, but we would like to work with unfixed virus. So
far I tried 100-500 mM MgCl2 and dextran without success.

Regards,

Juha

-- 
Dr. Juha Huiskonen
Max Planck Institute of Biochemistry
Department of Molecular Structural Biology
Am Klopferspitz 18
D-82152 Martinsried
Germany

Tel: +49 89 8578-2632
Fax: +49 89 8578-2641
GSM: +49 176 20786875
http://www.helsinki.fi/~huiskone/