The culture collections not only accumulate a valuable pool of genetic resources in the form of microbial strains but they are applying proper methods for preservation to prevent loss or genetic change of these strains.
For security reasons, and to minimize the probability of any strains of patent deposit being lost, each strain should (whenever practical) be maintained by at least two different procedures.
We are using two methods simultaneously to maintain permanently the same strain, freeze-drying (lyophilization) and cryopreservation (storage in liquid nitrogen), which are reliable methods for minimizing the risk of genetic change.
The freeze-dried strains are prepared at least 25 copies per strain in double glass-vials, which are closed under vacuum. Viability is checked regularly. A few straws or plastic tubes per strain are kept in liquid nitrogen as “master culture”.
Strains deposited for patent purposes are kept separately and stored in locked room.
In the technical and administrative procedures at the NCAIM we follow the basic protocol for a deposit under Budapest Treaty as it is specified in its statutes.
Records relating to the strains are kept in metal safe and only authorized staff has access to both the strains and the records.