Need Help With Identifying Contamination
Hellooooo.
So a bit of a background; we are trying to grow cell cultures & organoids in a medium consisting of:
10% FBS
1% P/S
Rest is DMEM.
However, some tiny little creatures have some other things to say. Almost every single medium, with or without the cell cultures in place, get 'murky' at some point and we start observing a bacterial culture (the same one each time) in them. We cleaned the incubator and even tried a new one, tried different FBS and DMEM in case we got a lame batch (we also filter them beforehand to make sure), cleaned the hood and I have to say we follow proper protocols for working in it.
Could you help me identify what these bacteria are? Or how we can identify the source of the contamination? The usual suspects are, at this moment, perhaps a resident contamination somewhere like a pipette or deeper in the hood, and ofc handling of the media and the cell cultures.
To give a bit more detail, we almost never stumbled upon a contaminated organoid except once or twice, and not all the media get contaminated always - but the ones that do show a clear contamination around a week-2 weeks after we plate the cells.
I added an image of the contamination in case there are any microbiologists out there that trust their visual identification skills, I don't trust mine :) I can also send a video but I couldn't figure out how to upload it here.
Thanks in advance and I wish you all the very best of dayss.