Presumably you want Mn2+ , but you need to specify.
If so, you need to make it up fresh, and keep it at a pH below 7 if at
all possible, as it oxidizes readily.
Bis-tris will weakly chelate it and slow the oxidation process.
On Apr 6, 2009, at 11:14 AM, Matthew Alan Bratkowski wrote:
> Hi.
>
> Does anyone have experience using solutions containing manganese as
> crystallization buffers (buffers, not screening well solutions)? The
> protein that I am working requires manganese for activity, and I
> have read
> reports of related proteins crystallizing in manganese buffers. I
> made a
> buffer containing 3 mM manganese, that initially had a black color
> then
> turned to deep purple, and later almost clear. After a few weeks, the
> buffer turned an orange color and contains dark manganese syrup on the
> bottom. Does anyone know how to prepare a manganese buffer that is
> stable
> enough to be used as a protein buffer for crystallization screens?
>
> Thanks,
> Matt
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