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LB with or without antibiotic - (Feb/09/2006 )

Dear all,
I have one question about adding antibiotic into LB when doing transformation. After you can select positive colony (white colony) and then you innoculate this colony in 3 or 5 ml LB. Do you add antibiotic in this 3 or 5 LB? If you don't add it, it have any problem or not?

Thank you for your help



sure you must add Atb in you mini- and even maxi-cultures to avoid growing of satelites and to maintain resistance of the desired transformed clones

i also think that you shoul store your cultures longer in the fridge w/o contamination if Atb was added...



starting from a colony and doing a liquid culture without any Atb will drive a strong plasmid loss. It's not as in cells in which resistance means integration of the plasmid in the genome...


definitely add...unless u have loads and loads of time and dont know any good way to spend it ...