> I have been trying to work out how to estimate transformation
> efficiencies but in my searching through various texts I have found 3
> different (and confusing!) ways which all give different answers!. Could
> you please tell me if the calculation written out below is correct?
>> 200µl of E. coli are transformed with 1ng of pBR322, made up to 1ml with
> growth medium for the recovery phase and then 10µl of this plated plated
> out (i.e. 1% of the total transformation mixture, therefore equivalent
> to 10pg DNA used) and 100 colonies obtained. Is the transformation
> efficiency 1 x 10(exp)7 cfu/µg DNA? (i.e. 100 colonies per 10pg DNA and
> therefore 10,000,000 colonies per µg of DNA).
>> Kevin Mulcahy.
>You are right.