[ccp4bb]: Ammonium selenate for Se labelling of proteins

[Allan Matte <allan@bri.nrc.ca>]

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Hi,

Could someone please advise me on the following questions:

1. Has anyone experience growing E. coli (or other cells) in media
   containing ammonium selenate to Se-label proteins, as an alternative to
   Se-Met ? The advantage, of course, is that you would not have to use
   a Met auxotroph for expression, plus you get the Cys residues
   Se-labelled for free. If so, do you have a favourite recipe (defined
   media versus undefined, [] of ammonium selenate, etc.). I have seen
   only one supplier so far for ammonium selenate (Alpha Aesar, Ward Hill
   MA, USA Tel: 1-800-343-0660). 

2. Related to the above, do many people find it is necessary to use a Met
   auxotroph at all ? It sounds like some people use SeMet in the medium
   with their normal expression strain, with good levels of SeMet
   incorporation. I'd be grateful for opinions on this approach.

Thanks in advance for your response,

Allan Matte

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| Allan Matte			    |	e-mail: Allan.Matte@BRI.NRC.CA |
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