»Tales of the Tiny« – Secrets Preserved

For approximately 3.5 billion years, bacteria have inhabited nearly every environment on Earth — from deep-sea hydrothermal vents to polar ice. Their extraordinary adaptability reflects a remarkable form of “cellular intelligence” and an immense biotechnological potential.
For a long time, microorganisms were primarily perceived as threats. This perspective changed fundamentally with the accidental discovery of penicillin by Alexander Fleming, revealing that microbes can also be powerful allies. This breakthrough sparked global efforts to systematically collect and study microbial resources — leading to the establishment of major biobanks worldwide.

At Fraunhofer IME, we currently preserve more than 130,000 bacterial strains in cryogenic storage. Each strain represents a potential key to novel natural products, innovative active compounds, and sustainable biotechnological solutions.
Through »Tales of the Tiny«, we invite you to explore:

• Which natural products are produced by our microorganisms?
• Which applications are already shaping industries today?
• And what untapped innovation potential lies ahead — for pharmaceuticals, agriculture, environmental technologies, and industrial biotechnology?

Join us on this journey into the invisible world — and discover with us the solutions of tomorrow!

Imagine a library—but instead of books, its shelves hold living organisms, each carrying a unique biological story shaped over millions of years of evolution. That is, in essence, what a microbial collection is. And like any great library, its value depends on careful preservation, maintenance, and accessibility for future generations of researchers.

Built over more than 80 years in collaboration with partners from academia and industry, our collection today comprises more than 130,000 bacterial and fungal strains. These microorganisms originate from some of the planet's most remarkable habitats: ocean floors, deep-sea coral reefs, forest soils, oil reservoirs, lichens, sponges, sea anemones, and insects. Every strain could hold the key to a new medicine, more sustainable crop protection, or innovative industrial biotechnology.

Collecting microorganisms, however, is only half the challenge. Preserving them for decades while maintaining their purity and genetic stability requires a science of its own. Without appropriate storage, microorganisms can mutate, become contaminated, or simply die—taking with them the very characteristics that made them valuable in the first place.

Four Methods – One Goal

No single preservation method is suitable for every microorganism. Instead, we combine four complementary approaches, each serving a specific purpose.

• Cryopreservation (-150 to -196 °C): Our gold standard for long-term storage. At liquid nitrogen temperatures, biological processes come almost completely to a halt.

• Ultra-low freezer storage (-80 °C): Provides rapid access to working cultures for everyday research.

• Freeze-drying (lyophilisation): Similar to the process used to make instant coffee, water is gently removed from living cultures, leaving them in a stable, dry state that can be stored for years in sealed glass ampoules. Our collection currently contains more than 20,000 such ampoules.

• Sterile soil preservation: Particularly suitable for spore-forming soil bacteria, recreating conditions similar to their natural environment.

Together, these methods allow us to preserve the remarkable diversity of our collection safely and efficiently.

Protecting Science Through Redundancy

No preservation system is entirely immune to failure. Equipment can malfunction, and unexpected events can occur. To minimise these risks, every strain is preserved multiple times using different methods and stored at different locations. In total, our collection contains more than 700,000 vials, ensuring that valuable biological resources remain protected for future research.

Supporting this archive is an extensive infrastructure of liquid nitrogen tanks, ultra-low freezers, and automated monitoring systems that continuously track critical storage conditions. Around the clock, a dedicated on-call team stands ready to respond whenever human intervention is required.

Preserving More Than Microorganisms

Alongside the physical collection, we are building its digital counterpart. To date, the genomes of more than 400 strains have been sequenced, with the long-term goal of extending this digital archive across the entire collection. Together, physical preservation and genomic information create an increasingly valuable resource for future scientific discovery.

Maintained according to internationally recognised quality standards, our collection supports researchers and industry partners around the world in developing tomorrow's innovations.

Because every vial in our collection preserves far more than a microorganism. It preserves millions of years of evolution—and the potential for discoveries yet to come.

Same white coat. Very different careers. 

When Penicillium was named “Microbe of the Year 2026” by the Vereinigung für Allgemeine und Angewandte Mikrobiologie (VAAM), it was a reminder that this genus is far more than the source of antibiotics. 
In our biobank, we preserve over 1000 strains representing 265 species of Penicillium. Even within this small snapshot, one striking observation stands out: many strains look remarkably similar, white, fluffy colonies with the characteristic brush-like structures, yet their functions can differ profoundly. Our oldest isolate, dating back to 1940, is a Penicillium notatum, the species from which Sir Alexander Fleming first isolated penicillin. Starting with a random observation - and the right conclusion - this fungus sparked a medical revolution. 

In principle, the laboratory and the kitchen share more than one might think; A dedicated workbench with specific tools, precisely measured ingredients or chemicals, and selected microorganisms that drive transformation. Penicillium nalgiovense is widely used in dry-fermented sausages, where selected strains support surface maturation and contribute to the development of texture and aroma. Likewise, Penicillium camemberti and Penicillium roqueforti shape the distinctive character of soft and blue cheeses. In these contexts, Penicillium is not a contaminant but a carefully selected partner in food production. 

Yet even within similar white colonies, new functional paths emerge.
Our collection also includes a Penicillium strain that exhibits a very different trait. Under solid cultivation conditions, the strain produces a microbial substance known as a resorcinol. As part of the BMBF-funded MbioShrimp project, we are exploring its potential to inhibit tyrosinase, an enzyme that triggers browning in shrimp, much like the browning of a sliced apple. Browning is currently often controlled using sulfites, which are increasingly questioned due to possible intolerances. Developing safe, bio-based tyrosinase inhibitors could help reduce the use of sulfites and improve post-harvest preservation. 

From antibiotic discovery to traditional fermentation and emerging strategies for sustainable food systems, Penicillium demonstrates how microbial diversity connects laboratory innovation with everyday life.