Worm like contamination (see photo) - serious problems (Jun/28/2007 )

We are doing our best for aseptic techniques. we three persons has been facing same problems...handling has been a very less chance--we guess...but dont know exactly.

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Throw the cells away and start again. As the bearer said in his post, G418 and other antibiotics will either kill or harm your cells. You will also be selecting out cells which are more resistant to this insult.
Another thing to be aware of is that the cells will be expressing different proteins because of the bacterial toxins being released. These protiens do not always disappear when the infection subsides.

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Thanks to you all for your valuable discussion and time.

I did the same..discarded all the solution and media, decontaminated the working areas and incubator.

But still I suspect the very few such contaminations in my new culture flask (it gonna destroy my all stocks and efforts too??)

So, I wanted to know what actually these are (if you guys previously having the same problem or have overcome or known from any literatures or evidences)??

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did you use antibiotics? it is the only way to get rid off bacteria...

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yes we use 1% penicillin/streptomycin.

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do you try to plate out the contaminated media/culture on an agar plate? a normal LB agar? do some simple test to see what kind of bact is it? i'm worried that your stock is contaminated.

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Thanks for your kind attention Sanjiun.

I will try to culture the cells and stain (Grams or simple) or will do some tests as per your suggestions. Since the contaminated creatures are multiplying rapidly and motile (seems under microscope) and also nearly rod shaped, I am now suspecting they are no other than bacteria and most probably E. Coli or lactobacillus acidophilus (to be confirmed first).

But I am worried how come they are growing well in 1% PS condition??????????????

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Since you are using Pen/Strep routinely it is possible that bacteria get resistant to them. Try using Gentamycin to clean your culture, worked well for me even when Pen/Strep had no effect at all....

Stardust

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Stardust, you are right but Rhombus alarmed about the possible harms of using gentamycin (see his reply).

You dont have problems using Gentamycin (both about contamination and other cell related experiments)??? Please let us know.

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As far as i can see Rhombus was talking about G418 (Geneticin) not gentamycin...I have cleaned cultures of primary cells and cells lines (human, hamster) with gentamycin. I tried 70 µg/ml first which harmed the cells but 50 µg/ml was ok, after 2 days the contamination was gone and did not return after ending the treatment. Longer treatment lead to slow growth of the cells which could be reversed by stopping the treatment.

Stardust

Edit: I used gentamycin which is tested for cell culture cells so there shouldn't be any problems about the purity

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