HELP: dialysis of protein

[Christine Hughes]

In article <3isvc7$d8m at nic.umass.edu>
nzheng at titan.oit.umass.edu (NZ) writes:

> NAME RAVI PRAKASH .D (sl16s at cc.usu.edu) wrote:
> : Dear Netters,
> : I have attempted to dialyse a recombinant protein (in 0.5M NaCl, 300mM
> : imidazole, 6M urea) into buffer with 150mM NaCl, 20mM tris, 2.5mM CaCl2. Within
> : few minutes of dialysis there is a precipitate formation in my dialysis bag.
> : Can anyone have any suggestions as to how I can rescue my protein from the
> : precipitate? Or any better way to dialyse the protein in future?
> : Thankyou in advance for any suggestions or comments.

You could try dialyzing away the urea over 1-2 days in a stepwise
fashion, maintaining high salt (1M NaCl) and 10-20% sucrose through
each of the urea conditions -- you can dialyze away the salt and
sucrose after the urea is gone

Christine
Dept of Biochemistry
hughe014 at mc.duke.edu