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bacterial transformation kit life-technologies - (Jan/10/2014 )

Hi you guys, 


I did my transformation yesterday. I supposed that pUC19 supplied in the kit is for the positive control. 

Strikingly, I had few (around 50 colonies) in this positive control (pUC19) but a several hundreds with my plasmid (after gateway LR reaction). 


Do you have any explanation for my case? 


Thanks in advance.




Hi Trang.  Unless your plasmid was also pUC19 and you used the exact same amount, then you are not really looking at a comparable control.  Colony counts can be interesting to do, but they rarely provide any useful information.  The results from a screen (either digest or PCR) of colonies on your experimental plate are more important.