"Richard Buick" <Richard.Buick at btinternet.com> wrote:
>Hi
>I wonder if anyone could suggest a method for the separation of active from
>inactive (mis-folded) protein. Affinity chromatography is not an option
>since the method must be applied to many different proteins. Ion exchange
>and hydrophobic interaction have been tried with not much success. The
>proteins to be separated are post IMAC.
There is really no general solution for this task. Of all I am aware of,
hydrophobic interaction would be the best candidate for the task because
the same sequence folded differently almost certainly results in different
hydrophobisity. If one set of conditions failed to separate, it does not
mean that another will.
Barring affinity purification, other alternatives would include differential
precipitation (salt, PEG, solvents) but in any case this will have to be
optimized for every individual protein. Also, some misfolded proteins form
soluble multimers - gel filtration in this case.
DK
