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Satellite colonies - (Jul/10/2006 )

If satellite colonies form near blue colonies in blue white screening, will they be blue or white?


usually satellite colonies are not true clones. If you restreak a single colony on selective media, they will most likely die or be very unhealthy and unusable. I suspect since satellites do not carry a plasmid they would be white.


Most satellite colonies would be white, as vasussci said, as they are competent cells that didn't take up any plasmid during the transformation, but could nonetheless grow up in the halo of deactivated antibiotic around the plasmid-containing, antibiotic-resistant colony. Pick only well-isolated colonies at all times.


When you transform with a lot o ligation product or you don't extend it properly over the plate, some times, you obtain a lot of colonies together, they grow up very near ones of the others and some of them are very little and they look like satellites.

-aztecan princess-