vector propagation in E coli - (Jul/19/2014 )

Hello,

I tried to propagate a vector called pFBDM in E coli. According to vector map, the vector carries both ampicillin and getamycin genes. Below is the result.

The competent cells were transformed with 10ng of plasmid, after heat shock , the cells were allowed to recover in SOC for 45min.

LB+ampicillin ( 100ug/ml): colonies growed

LB+ampicillin ( 100ug/ml)+ gentamycin ( 7ug/ml) : no growth

I am using same batch of competent cells, the cells are definitely good.

Thanks for your answer.

Hazarding a guess, but it is quite likely that the gentamycin gene will take a while to be expressed - you could try 1.5 hours recovery and see how you go.  Note that you should only need to select with one antibiotic if you are only inserting one plasmid.