Frequently Asked Questions


All ATCC microbial strains are considered to be at passage zero.

We recommend no more than 5 transfers or passages be made from an ATCC Genuine Culture®. Repeated passage or serial culture increases the risk of contamination and can result in undesirable genotypic and/or phenotypic changes.

The passage number is unknown because the cells were deposited to ATCC with an unknown passage.

Lyophilized cultures can be stored at temperatures below 4C for extended periods of time. Storage above 4C is not recommended as prolonged exposure to temperatures above 4C is not beneficial to viability of the culture.

For storage of cells after subculturing, you may need access to either a freeze-dryer or a -80C freezer. Many bacteria can be stored at -80C in glycerol for years without a significant drop in viability. It is not recommended to store glycerol stocks of bacteria at -20C, however. Freeze drying bacteria would also allow it to be kept at temperatures below 4C. I've attached our bacterial culture guide to this email which also has information about cryopreservation and storage of bacteria cultures.

COAs can be downloaded from ATCC Homepage in the tab “Technical Support”.

you can listen to past ATCC Webinars at any time. Just click Webinars from the ATCC Homepage and select the year(s) you are interested in viewing

ATCC warrants that (a) cells and microorganisms included in the ATCC material shall be viable upon initiation of culture for a period of 30 days after shipment thereof from ATCC and (b) any ATCC Material other than cells and microorganisms shall meet the specifications on the applicable ATCC Material product information sheet, certificate of analysis, and/or catalog description until the expiration date on the applicable ATCC Material’s product label (such thirty (30) day period, or period until the expiration date, referred to herein as the “Warranty Period”).

Yes, ATCC offers different types of stem cells, including human induced pluripotent stem cells, human mesenchymal stem cells, mouse embryonic stem cells, as well as associated stem cell culture reagents and media.

Yes, ATCC offers cost-effective testing services for mycoplasma detection and human cell line authentication (STR analysis).

With ATCC’s Mycoplasma Testing Service, DNA staining and direct culture methods are performed simultaneously for each sample. Together, these methods can detect mycoplasma infection for most of the known species.

ATCC has several drug-resistant strains available. Some of our more popular strains include methicillin-resistant Staphylococcus aureus (MRSA); Vancomycin-resistant Enterococci (VRE); Carbapenem-resistant Enterobacteriaceae (CRE), including NDM and KPC strains; Extended-Spectrum beta-lactamase (ESBL) strains; drug-resistant Acinetobacter baumannii, drug-resistant Pseudomonas aeruginosa; isoniazid-resistant mycobacteria; drug-resistant Candida albicans; and drug-resistant vector-borne parasitic protozoa, including strains of Plasmodium falciparum. For more information about superbugs, please visit our website at To view a complete listing of our multidrug-resistant strains, visit us online at, or download a copy of our Multidrug Resistant & Antimicrobial Reference Strains brochure.

Yes, ATCC provides culture media for all our hTERT-immortalized cell lines. You can find the recommended culture media for each cell line of interest on the specific ATCC webpage and on the product sheets.

Yes. Upon successful execution of a new material transfer agreement, materials received previously will now be subject to the new transfer policy.

There is no termination clause in the MTA. The continued use of Biological Materials shall be governed under the MTA.

ATCC Materials available through the general collection at ATCC are governed by the MTA, which stipulates that use of ATCC Materials be for research use only. Any commercial use would be permitted through ATCC either directly or through the Contributor of the ATCC Material.

Yes, reporting a transfer of an unmodified derivative or a modification is required, under the transfer policy in the MTA, whether it is for a transfer to a researcher at an external third party or to a researcher at the same institution. The transfer is permitted in instances where the investigator originally receiving the material is collaborating with the researcher either at their institution or at another institution. In addition, where an investigator published on the unmodified derivative or modification and wishes to transfer the material to researchers for further development in relation to the publication, such transfer is permitted. Transfers can be reported, within two weeks of the actual transfer.

ATCC does not sell any of these.

We have ATCC Genuine Cultures® and Preceptrol® cultures at BSL1 levels.

Each of the guides is available free from charge on our Resources for Microbiology page. They are provided in an easy-to-print PDF format.

CFU/vial represents the number of live bacterial cells within a single vial that are able to form colonies. Bacteria/vial indicates the number of genomes in the sample per vial.

ATCC uses 10% glycerol for our ATCC® Minis.

Yes, ATCC plans on releasing strains later in the spring of 2015 in the ATCC® Mini format that are aligned with VITEK® 2 cards from bioMérieux.

Our real-time testing has so far demonstrated that ATCC® Minis are viable up to 2 months at -20°C. We plan on continuing this testing through 1 year to assess long-term viability at this temperature.

Yes, -70°C is an appropriate temperature to store ATCC® Minis.

ATCC® Minis are at passage zero.