dlaw at idgplc.com
Fri Oct 6 02:33:29 EST 2000
Antani <lab2NOSPAM at plantechno.com> wrote in message
news:xUZXHuhLAHA.120 at newsmst.mcis.galactica.it...
> Hi there!
> Maybe this is a stupid question but....someone could tell me what is the
> best way for have long-term storage yeast stocks ?
> I've found discordant answers to it....
> Thanks a lot
Freezing of cultures is the best long term bet, -80C is better than -20C.
Some books recomend suspending yeasts in water and storage at room
temperature. They do survive for several years like that , but sometimes
their properties change. In a former job I stored a range of yeasts
resistant to several antifungal antibiotics. When I got them from the water
cultures 6 months later they grew fine but had reverted to being sensitive
to the antibiotics. Presumably without the selective pressure they had
reverted back to a susceptible phenotype. We later reverted to freezing
cultures and never noticed any changes in antibiotic resistance in frozen
So if you want to maintain the yeast's phenotype FREEZE!!
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