Help needed in screening libraries.

Mic Chaudoir mic at
Fri Jul 21 10:53:29 EST 1995

In article <3uld9e$nnl at>,
mbxrh at (Richard Hastings) wrote:

> Does anyone have any idea how many plaques I need to screen to have a
> good chance of finding a full length gene that I'm after? 

It depends partially, on how abundant the mRNA you are after is.  However,
the library should have some indication of how manyt independent clones
arein it.  We usually try to screen about 2X this number (which is
typically 2X10^6)

 It's a moth
> cDNA library cloned in lambda phage.  Also how many plaques is it best
> to use on a single plate of 150mm diameter?

Most people plate out 50,000 plaques/big plate.

> Thanks in advance for any help you can give me.

Also, make sure that you use agarose in your top agar, instead of agar. 
It helps to minimize sticking of the NC to the top of the plates.

Name:Mic Chaudoir    
E-mail:mic at
"I'm close enough to trip the wire"-KMFDM
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