How many transformants should we select for screening? - SDM, QuikChange Lightning SDM Kit (Oct/23/2008 )

Hello,

I just started my SDM experiments and luckily, on my first try, I got colonies already. So I'd like to know, how many transformants should we select for screening? I am using QuikChange Lightning SDM Kit (Stratagene) and my plasmid size iz approx. 8.5 kb.

Many thanks,
znb21

I usually compare with the control plate and then decide. If the control plate is clean (i.e. no colonies) then I pick 5 colonies for confirmation. But if there are few colonies on the control plate then I pick 10. If the number of colonies on control vs positive are half then I discard and set up new reaction.