contamination - (Jun/28/2014 )
Hi,
I had two dishes of iPS cells. In one of the dishes, I observed a mold-like colony which looks like a fuzzy ball with small protrusions all around and the iPS cells were dying. I discarded it and now the other dish had these vibrating small black dots (see attached image), many of them. The cells in this dish is also dying. I use pen-strep in the medium and so I don't think it is a cell-wall bacteria. Any idea what kind of contamination this is? Mycoplasma or mold or something else?
Are they really moving or just vibrating with the fluid (then it could be debris) ?
Anyway, have a look at these threads too:
http://www.protocol-online.org/forums/topic/21330-black-dots-contaminant-phenonmenon-helpful-paper/
They don't seem to be moving with the media...they are vibrating on their own. And there are too many black dots; usually the cells do not have this much of debris. Coupled with the fact that the cells are dying, this is highly likely a contaminant but im not sure what type?
Did you take a look at the threads ? It could be the discussed Achromobacter.
BTW, mycoplasma are not normally visible.
"Vibration" per se could be Brownian and probably isn't that relevant. If it;s bacterial, there's nothing to say it's Achormobacter over any other. Try to culture the stuff.