Stability Bead-Avidin-Biotin-DNA?

[Chih-Lin Hsieh]

Hi Jim,

We are working on a project that may have a similar step as what you  
were doing, and I come across your posting.  Have you gotten any  
information on how stable the streptavidin is in formamide?  Did your  
DNA (I assume it is biotinylated) bind to the streptavidin in 64-84%  
formamide?  Do you know whether strpetavidin becomes denatured in  
formamide?  I am a bit puzzled by your description of white ethanol  
precipitate is washed off the beads when incubated with formamide.   
Was there a EtOH ppt step after formamide incubation or this white  
ppt occurs in the formamide incubation?  Thanks for any information  
that you can share.

Chih-Lin