FAQ - microorganisms

All information we have on a strain can be found in the databases of the DSMZ Digital Diversity platform. To facilitate access to relevant strain information, there is a direct link to associated data on the right side of each strain entry in the online catalogue.

A type strain is defined in the “International Code of Nomenclature of Bacteria” as the “nomenclatural type of the species”, and is the "reference point" to which all other strains are compared to know whether they belong to that species. Type strains are marked as such and can be searched by ticking the relevant box when conducting a catalogue search for e.g. bacteria.

One reason may be that the strain has been lost or, after publication of the description, turned out not to show the characters given for the taxon. In rare cases it may happen that a strain has to be checked and is therefore temporarily not visible in the catalogue until clarification. Also, it may take a while for a strain to be released to the online catalogue after publication. Another reason may be that the strain was deposited for patent purposes. These strains and their data are kept confidential by the DSMZ.
Please contact us via the customer support form to find out the reason for the lack of showing in the online catalogue.

The history of a strain (as far as known to the DSMZ) can be found in our online catalogue in the individual strain entries. The information is given in chronological order, with the most recent holder of the strain to the left, the oldest holder of the strain to the right.

The forms of delivery are indicated for every individual strain in the respective strain entry in our online catalogue. In case a strain is not available in freeze-dried form, it will be sent as an actively growing culture.
If you order an actively growing culture where a freeze-dried culture is available, the fee is higher due to the additional work required. Some organisms can also be requested as frozen aliquots (delivered on dry ice). If you cannot find this option in the catalogue, please ask our sales department (sales(at)dsmz.de). For details please see our price list.

In some cases, the ZKBS (Central Committee on Biological Safety), the responsible organ for the classification of biological material in connection with genetic engineering, classifies an organism differently than the TRBA (Technical Rules for Biological Agents). The DSMZ wants to inform its customers about an allocation in a higher risk group to make them aware that the organism might pose a higher risk than its legal allocation according to the Federal Institute for Occupational Safety and Health (BAuA) implies.

No, the DSMZ does not certify such data. The providers of media and other products may be in a position to certify this information. The DSMZ only uses high-quality providers' products. Please, also remember that according to our Terms & Conditions microorganisms supplied by the DSMZ are for in vitro use only.

A strain-specific certificate of authenticity, origin and quality is printed on each delivery document.
All lots of our strains are checked for strain authenticity with strain-specific methodologies. Additional information is not generally provided.

The DSMZ provides a comprehensive, general, not strain-specific safety data sheet. A strain-specific certificate of authenticity, origin and quality is printed on each delivery document.

A freshly cultivated cell suspension of the microorganism is either dropped onto a pre-dried protectant/carrier or the culture suspension is mixed with a liquid protectant/carrier. Depending on the strain, different protectants/carriers are used leading to the different appearance of some of the pellets. In most cases, the protectant/carrier is the main component of the pellet. Therefore, when initially re-activating the strain the whole of the pellet must be resuspended and transferred into a small volume of medium (5-10 mL) so that the number of cells is sufficient for subcultivation.

The cell numbers present in a pellet differ due to strain-specific preservation conditions. Each lot is routinely checked for strain viability so that the DSMZ guarantees that a sufficient number of cells are present to allow successful reactivation and subcultivation.

All DSMZ ampoules are double vial preparations, sealed under vacuum. The outer vial has at the bottom humidity indicators consisting of blue or red Silica Gel. In the past some red Silica Gel batches did react inhomogeneous with a coloration varying from red, orange and colourless globules. This inhomogeneous coloration does not indicate automatically humidity inside the ampoule and influence on the viability or quality of the dried culture. We recommend opening and rehydration of the dried cultures in the inner vial even in case of ambiguous coloration of the Silica Gel. In case of problems during cultivation, please contact our customer support.

Several strains of fastidious microorganisms, especially strictly anaerobic bacteria, are suspended prior to lyophilization in a protectant mixture containing ferrous sulphide or charcoal, which gives the pellet a black colour.

Bacterial cell suspensions are dried together with a protectant. The pellet can be rehydrated for initial revitalization whereas phages are dried as suspensions on filter paper strips and require their host strain for initial propagation.

Our freeze-dried microorganisms in glass ampoules are batch no. zero, actively growing cultures are batch no. one.

The preservation date on the inner vial is the lot identification. Viability and authenticity of each strain is routinely tested at the DSMZ so that ampoules that are several years old can be used without problems. Actively growing cultures are freshly prepared before dispatch.

The DSMZ does not set an expiry date on freeze-dried cultures. Our Terms & Conditions state that all cultures are meant for immediate use only, indicating a warranty period of four weeks. Most freeze-dried strains can be stored for a much longer period, especially when kept under optimal conditions. However, the DSMZ will not certify a fixed date after which ampoules have to be discarded.

At the DSMZ, freeze-dried ampoules are stored at 10°C in the dark. According to our Terms & Conditions, the material is to be used immediately upon receipt and the DSMZ can only accept claims for products where tests for viability have been made immediately after receipt. The DSMZ accepts no responsibility for the viability of material stored for extended periods of time (more than four weeks) outside of the DSMZ.
When possible, the DSMZ ships strains of microorganisms that have been dried under vacuum. While the DSMZ uses the generic term "freeze-dried" the actual methods may deviate slightly. Strains shipped as "freeze-dried" vials are usually stable when shipped without cooling or in dry ice. Excessive temperatures should be avoided.

The complete pellet of an opened ampoule has to be resuspended immediately in the appropriate medium given in the strain entry in our online catalogue, otherwise the cells will die rapidly. Therefore, it is necessary to have the appropriate culture medium ready before receiving the culture. Detailed information on the cultivation media you need for your strain(s) is available from the strain entry in the online catalogue as well as from our database MediaDive. The latter also provides detailed information about the medium recipe and its production process.

Actively growing cultures have to be sub-cultured under the correct conditions immediately after receipt. Psychrophilic and mesophilic microorganisms should be kept in the refrigerator before they are used unless otherwise stated. Especially sensitive, hyperthermophilic or obligately acidophilic strains should be kept at room temperature until used.

No, the DSMZ does not sell cultivation media. Detailed information on the cultivation media you need for your strain(s) is available from the strain entry in the online catalogue as well as from our database MediaDive. The latter also provides detailed information about the medium recipe and its production process.

Detailed information on the cultivation media you need for your strain(s) is available from the strain entry in the online catalogue as well as from our database MediaDive. The latter also provides detailed information about the medium recipe and its production process.

All entries in our online catalogue indicate the cultivation conditions used by the DSMZ. These include both the medium and temperature used in the DSMZ for cultivating the strain. We recommend that only these cultivation conditions be used when initially re-activating a freeze-dried strain or for the initial sub-culturing of an actively growing strain.

Additional information about the used cultivation media (recipe, production, …) can be obtained from our MediaDive database.

Special tips for cultivating certain groups of organisms can be found here.

Please follow all instructions provided on the "Handling and Safety Information" brochure accompanying your cultures consignment regarding the re-activation of freeze-dried strains. This information is also available as download here.
We also provide video tutorials for handling aerobes and anaerobes.
Additional information on a variety of other organisms including myxobacteria, streptococci, enterococci, methanogens, acidophiles etc. can be found here.
Actively growing cultures are best sub-cultured using the medium and growth conditions listed in our online catalogue under the strain specific information or use our MediaDive database.

Generally, use the recommended medium without the addition of agar. For fastidious microorganisms which grow only on solid media (e. g. M 693; M 429; M 585) use complex liquid media like M 1; M 545 or M 92. Please keep in mind that the organisms DO NOT GROW in these liquid media.
It is better to use any peptone or casamino acid or yeast extract containing medium than water or buffer for the solubilization of the pellet.

For many fastidious organisms a higher inoculum is needed to reactivate them. Add 0.5 ml of adequate liquid medium (given for each strain in its specific strain entry in the online catalogue) to the pellet and dissolve the pellet as quickly as possible, then dilute the suspension with 4.5 ml of the same medium. For strains that grow only on plates but not in liquid media, distribute at least 1 ml suspension on each agar plate. If the strain grows also in liquid medium use 1 ml for inoculation of 5 ml liquid medium, plate the rest on agar plates also using 1 ml suspension per plate. In some cases, it is recommended to resuspend the material of one ampoule in 1 ml and plate it completely onto one single agar plate. Please check the specific strain entry in our online catalogue.

Once strains obtained from the DSMZ have been successfully sub-cultured in a customer’s laboratory these methods could be used for long-term storage. Since the DSMZ holds more thousands of bioresources it is impossible to give exact details for each strain. The DSMZ generally stores the majority of its bacteria and archaea in liquid nitrogen and/or freeze dried. Some strains are also stored at -80°C.

The methods used by the DSMZ and in other collections for long-term storage of Bacteria and Archaea have been published here:
Day, J.G. & Stacey, G.N. (2007). Cryopreservation and Freeze-Drying Protocols. Methods in Molecular Biology Volume 368, chapter Vacuum-Drying and Cryopreservation of Prokaryotes. doi.org/10.1007/978-1-59745-362-2.
In addition, useful information is provided by the CABRI guidelines.

Please contact the relevant collection expert.

Deposit of biological material in the public collection of the DSMZ is free of charge.
Charges for the deposit of strains for patent purposes or as a safe deposit are provided in our price list.
Information about the different types of deposit can be found here.

Please follow the steps described here exactly, use our accession form and please do not send us cultures without contacting us first.

The DSMZ provides detailed information under safety instructions. Please make sure that the material you are sending is properly packed in a triple containment packaging system that is approved.

Growth media should contain those agents selective for the plasmids to avoid plasmid loss.

No, plasmids are only offered within their host bacterium.

No, we refer to published literature that are given as a DSMZ literature reference number for most plasmids.

Comprehensive information on phages, phage-specific methods and a separate FAQ list on the phage collection can be found here.