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Frequently Asked Questions

How long before my request ships?

Most orders are shipped to the customer the same day the order is placed. Strains that need to be restocked or shipped in a metabolically active state will take additional time to process. Many strains are maintained as lyophilized preparations at 4°C. Cells are suspended in serum, dried down, and vacuum sealed.Some strains, however, require storage in liquid nitrogen vapor for long-term viability, increasing the strain processing time.

Is there a restriction on use of Strains?

While the NRRL has no restrictions on the use of the strains in the open or patent collection that have been patented or no longer fall under patent regulations, that does not exclude the possibility that other patent applications may have been filed for the use of this isolate or patents/applications that claim using strains of this type for a particular purpose or process. While the strain itself may not be currently patented, we really cannot provide any guidance on freedom to operate; that would depend upon how you wish to use the strain and what patents/patent applications already exist and would best be addressed by your intellectual property counsel. The only restriction we do have that is we do not allow third party distribution of strains. Any third party requesting a sample shall be referred to ARS NRRL Culture Collection. NRRL is a publicly funded collection and it is important that we document our impact to ensure continued funding. If at any point any of the strains lead to a discovery of innovation, we ask that you periodically update us on the use of these strains. This will allow us to more accurately quantify our impact.

Why can’t I find a strain?

Strains in the Patent Collection are not available in the Prokaryote or Fungi Catalog. Please see Patent Collection Policy (Strain Requests)for patent strains. If you are looking for a NRRL strain from a publication that you cannot find, email us and we will see if we have the strain. Some strains are removed from the public catalog if no longer viable or for restock purposes.

In what form do we accept strains?

All deposits must be submitted as an agar slant or plate. Please contact the Collection Manager to justify any reason your strain can not be deposited as an agar slant or plate and wait for alternative approval.

How do I get a required permit?


Animal Permit-APHIS VS. go to
Plant Permit-APHIS PPQ526 go to


You will need to contact the proper authority for your Country.