RNases A in sol. 1

[Jim Meador]

In article <Pine.3.89.9411231655.A18965-0100000 at gadwall.cs.uoguelph.ca>,
lgood at uoguelph.ca (Liam E Good) wrote:

> Hi,
> 
> Several alkaline lysis plasmid prep. protocols have been posted where the 
> first solution (sol. 1, PS1, etc., which is used to resuspend the 
> pelleted cells) contains RNase A.  Does anyone know the first reference 
> for this use of RNases A.  Also, does the procedure work because the 
> enzyme enters the cells and degrades the RNA before the cells are lysed 
> with NaOH/SDS?  I can't imagine that the RNase keeps working after the 
> NaOH/SDS is added.
> 
> Thanks in advance.  Please reply to me, because my subscription has been 
> getting interrupted.
> 
> Liam   

I am pretty sure that the rnase renatures upon KAc addition after
denaturing in the NaOH/SDS solution. It's a tough enzyme. It's also tough
to get rid of. I don't believe there is a reference.

Hope this helps,
Jim
meador at cts.com