Technical requirements and procedures
Form and quantity
CBS prefers to receive micro-organisms submitted for deposit as lyophilized
preparations. Where it is undesirable or impossible to supply lyophilized
preparations, active cultures growing in or on a suitable nutrient medium are
acceptable. The minimum number of replicates that must be supplied by the
depositor when making his deposit is as follows:
|
fungi |
12 lyophilized ampoules (preferably), or 2 agar slants |
|
yeasts |
12 lyophilized ampoules plus 1 agar slant (preferably), or 2 agar
slants
|
|
bacteria |
12 lyophilized ampoules plus 1 agar slant (preferably), or 2 agar
slants |
|
plasmids (in hosts) |
12 lyophilized ampoules plus 1 agar slant (preferably), or 2 agar
slants |
|
plasmids (purified DNA) |
minimum quantity of 50 µg |
|
phages |
10 ml with a titre of at least 109 pfu/ml |
In cases where the depositor is unable to supply lyophilized preparations, CBS
will prepare lyophilized cultures at the time of deposit from the material
supplied by the depositor.
Time required for viability testing
The average length of time required for testing viability is 2 weeks for fungi,
bacteria, plasmids and phages and 1 week for yeasts, but occasionally viability
testing may take longer, particularly if unusual antibiotics or other additives
are necessary in the medium.
Checking and renewal of stocks by the depositor
CBS routinely asks the depositor to check the authenticity of the
deposited preparations after subculturing.
New batches of cultures are prepared whenever it is necessary to renew
diminishing stocks.
Whichever method is used for preparing batches of samples for distribution, CBS
always keeps a portion of the original material supplied by the depositor.