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Unknown culture contamination? - (Jun/16/2006 )

I've been carrying out assays on 96 well plates with HCT116 cells. I went to harvest them today and in just one or two of the wells the media (DMEM) which is usually pink/orange was vivid green. I've never seen green wells before! I looked under the microscope and none of my cells were alive but there was something a bit like tiny seaweed....

Does anyone know what this could be? I 've obviously got contamination of some sort but nothing I've seen before.



It is bacterial contamination. I had got it before.


algae contamination......

-Minnie Mouse-

I've never seen green bacterial contamination in a cell culture! Its definitely fungal if its macroscopically green and filamentous. This type of fungus can be quite dificult to get rid of as they shed spores and will keep popping up in your cultures. If you see it in any other cultures (assuming your medium and other reagents are fine) I'd shut down your incubator and thoroughly decontaminate it.

Isolate and treat affected cultures with fungizone if they are precious, otherwise ditch them.


I dont think bacterial contamination looks green. Mostly likely fungal infection. Best thing is throw away all ur old cell culture solutions and start fresh with everything.
Also as karyotyper wrote, better decontaminate incubator too.


I wouldn't assume it can't be bacteria...Pseudomonas is pretty much ubiquitous in the environment and aeruginosa makes a pretty pigment...

but it's damn hard to get rid of and I would definitely do what you can to decon the incubator, hood, tubing, tools, ...


Perhaps someone slipped in some GFP plasmid for a joke. Or else, someone is using your plate to try to breed sea monkeys...


aspergillus fumigatus forms green spores ! perhaps its a fungal contamination. can only be clarified by microscopic examination