Very spall particulates vibrating in my culture - (Mar/28/2010 )
Can someone identify what kind of contamination this is?
They are black vibrating particulate. I found a video on youtube that shows something similar.
We thought it was mycoplasma and have been using Plasmocin at both manufacturer recommended concentration and higher, but haven't had any luck.
One thing I read was that they are actually a component of the cell membrane that is taking on autonomic properties. That this only happens with the degradation of cellular integrity and will soon cease.
It wouldnt be Mycoplasma as you will not be able to see Mycoplasma. You'd need a PCR or some other method to detect Mycoplasma.
I have observed similar particles and also thought I had contamination. It turns out that they are just pieces of FBS or cell membrane components moving via Brownian motion. If your cells arent undergoing apoptosis, necrosis or lifting off the plates (or even taking up typan blue stain) then your culture are fine.
Don't detect mycoplamsa with PCR it has too many false positives and false negatives. At a minimum use Hoescht 33258 staining, preferably followed by soft agar assay.
Cellular debris and other floating particles including most bacteria move via brownian motion. If the "contaminant is not multiplying, it is probably not bacteria, though there is a chance that it may still be.
Intra cellular bacteria, including mycoplasma will change the behaviour of cells in a subtle manner... just because your cells aren't dying does not mean they are OK!