I maintain the culture collection at a local college, and I’m in the process
of trying to preserve bacterial specimens in 20% glycerol at –80C. While I’
ve been successful with most of the cultures, I’ve heard that E. coli Hfr
specimens tend to lose their plasmids at temperatures this low. Is this
true? And if so, is there another medium I could use to preserve this
organism? (I don’t have access to a freeze dryer.) Any input would be
great!
Thanks in advance—
Pandora
