Storing E. coli -20 or -70

Nick Theodorakis nicholas_theodorakis at
Tue Nov 26 20:07:14 EST 2002

On Tue, 26 Nov 2002 04:07:47 GMT, "Bryan J. Maloney"
<cavaggione at> wrote:

>That depends upon how practical you consider lyophilization and storage of 
>those cultures in hard-vacuum vials.  I worked with a culture collection 
>that had 20-year old bacterial cultures stored at 4C in those 
>circumstances.  The cultures were first spun down gently to collect the 
>cells and resuspended in sterile skim milk.  They were then dried under 
>low vacuum (at room temperature, believe it or not) in that matrix and 
>then put under hard vacuum, then sealed under hard vacuum.  Every once in 
>a while, I would break out an old culture just to check viability.  I 
>believe the method was formally written up in John Tuite's methods manual 
>(actually an instructor's supplement to his plant pathology classroom 

I've received bugs from ATCC that seem to have been prepared this way
(or at least lyophilized somehow in milk). I suppose they might have
the details on their website.


Nick Theodorakis
nicholas_theodorakis at

More information about the Methods mailing list