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Detection on plate for a bacteria who express GFP? - (Oct/02/2006 )

Hello,

I realised a transformation in M. smegmatis with a plasmid who express the GFP.
Is someone else know an easy solution to see on the petri's dish which bacteria have the plasmid?


Thanks a lot

Biofred

-Biofred-

do your plasmids contain antibiotic resistance gene in addition to GFP?

-strawberry-

Put the petri dish under UV light for a very short period of time.

Hope this may help.

-Minnie Mouse-

Hello, yes my plasmid have a resistance to streptomycin so I used plates with this antibiotic. But I want to be sure before to test the colony because I have a lots of colonies.

-Biofred-

Hi Biofred,
you can check its by flourescence microscopy of transform bacteria. In our case we using its for H37Ra
transform with GFP gene and now able to see its by flourescence microscope on a slide.






QUOTE (Biofred @ Oct 4 2006, 02:54 AM)
Hello, yes my plasmid have a resistance to streptomycin so I used plates with this antibiotic. But I want to be sure before to test the colony because I have a lots of colonies.

-awadh-

Do you have an epifluorescent microscope? Take the plate and place it under the 10X objective lens. Using blue light excitation, you should see green fluorescence from the colony. I have done this many times and works very well.

-ML1975-

QUOTE (ML1975 @ Oct 11 2006, 09:29 PM)
Do you have an epifluorescent microscope? Take the plate and place it under the 10X objective lens. Using blue light excitation, you should see green fluorescence from the colony. I have done this many times and works very well.



Why epifluorescent microscope is needed ? I have tried and the colony do appear in green color and can be seen by eye

-lactamase-

QUOTE (lactamase @ Oct 29 2006, 04:55 PM)
QUOTE (ML1975 @ Oct 11 2006, 09:29 PM)

Do you have an epifluorescent microscope? Take the plate and place it under the 10X objective lens. Using blue light excitation, you should see green fluorescence from the colony. I have done this many times and works very well.



Why epifluorescent microscope is needed ? I have tried and the colony do appear in green color and can be seen by eye


If they express gfp strongly, then colonies will appear yellow and sure, that may be enough to prove they have taken up the plasmid. I have used gfp to make promoter fusions, and in these cases gfp expression can be variable. Using an epifluorescent microscope will allow you to detect low to moderate gfp expression.

-ML1975-