>
>However, treatment with urea is known to modify proteins (N-term/Lys/Arg),
>which could ultimately effect crystallization.
>
>Is this something that people generally worry about?
>For example
>-would you bother cleaning up the urea by ion exchange
>-get ultra pure urea (ultra $$$)
>-change to guanidinium chloride
>-hope that it might benefit crystallization (i.e. similar to methylation
>of lysines)
Have ~ 50 mM glycine or tris in your urea solution and prepare it fresh.
Then you don't have to worry about carbamylation.
Dima
|