Hi Filipp, Start a new culture from your frozen cell bank using disposable plasticwares. If it still happens and assuming the working environment is clean and operators follow the SOP, you may have to get a new cell stock from somewhere else.
We had a contamination once and traced back to its origin. It actually took a couple of weeks for the contamination to be visible. Whatever they were, just grew very slowly in the insect cell media. I guess you may not notice the contamination in smaller flasks when you pass the cells frequently. Letting the culture grow longer in large flasks accumulates the contaminants. Using AA adds cost. Better to make sure operators clean their gloves with ethanol. Very interesting picture. It could be a PhD thesis to figure out what it is. Good luck! Chun Chun Luo, Ph.D. The Protein Expert Accelagen, Inc. 11585 Sorrento Valley Road, Suite 107 San Diego, CA 92121 TeL: 858-350-8085 ext 111 Fax: 858-350-8001 [EMAIL PROTECTED] www.accelagen.com -----Original Message----- From: CCP4 bulletin board [mailto:[EMAIL PROTECTED] On Behalf Of Filipp Frank Sent: Friday, April 04, 2008 12:49 PM To: CCP4BB@JISCMAIL.AC.UK Subject: [ccp4bb] Off-topic: fungus contamination of SF9 cells Dear all, sorry for this off topic question. I am using baculovirus/insect cell expression and I have had persisting problems with contamination that seems to be some kind of fungus. I have a picture attached showing the filamentous structure of it. This contamination has persisted for a few months now and always seems to occur when we go to large 2.8 L flasks (however, there was also one instant where this was not the case). We have autoclaved all flasks for 90 minutes each and still we get contamination. Does anybody have experience with this kind of contamination? And what would you suggest for us to do? We will (again) disinfect our incubator and the hood. Also we are thinking about using an antimycotic/antifungal drug to get rid of this problem. Thanks a lot for any suggestion! Filipp
