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Does LB AMP XGal IPTG plates - for only Amp selection.. (Nov/30/2006 )

Ok, well it would be very nice of you all if you may help me on this
i have a standard plasmid with Amp resistance gene
Bacterias are Xl1 blue
I don't care about the blue white system.
I just want to select appropriate colonies and don't have time to pour LB plates (are mine were 'stolen' mad.gif) cause my brother from 10000km is still just in france for evening.
So are these plates ok?
What does mean the possible blue or white colonies if they appears?

May you help me please?
thanks in advance


The colonies that contain active LacZ are blue. white colonies have the LacZ gene disrupted (usually by whatever insert it is that has been cloned into the plasmid). very small inserts of foreign DNA may lead to light blue colonies.

LB plates should be fine. if you want to use the blue/white selection, you can add x-gal (prepared in DMSO) and IPTG (final concentration of 0.1mM) stock solutions ontop of the normal plates. Leave them for 30 min, so the solutiosn can absorb through the agar, and you're good to go.



In fact the plates already have ipgt and xgal, but i xant to use them just for the fact they contain AMP...
I will do tha and tell you what happen... blue white???? schtroumpf?


what happend to ur result fred??? know the result. may this knowledge will help in a hurry situation..........

-T. reesei-

sorry huh.gif i forgot to mention results.
Ok, my selection was good. My colonies are all white.
For ligation, that's not the result i expected (self religation) but the selection procedure is ok.