To protect themselves, organisms switch to stress mode in extreme environmental conditions such as heat, drought or high salt concentrations. Similar reaction routines take place in the cells of fungi, plants, animals and humans. But what are the fundamental principles behind these processes, and what changes in the cells ultimately lead to resistance and thus to adaptation to “uncomfortable” living conditions? Researchers from the departments of biology and chemistry at the TUK are now investigating this in the new STRESSistance Research Training Group. The German Research Foundation (DFG) is funding the project with around 3.9 million euros in an initial funding period over four and a half years.
“This is a remarkable success and another award for our education and research in the natural sciences. The funding will enable us to finance nine doctoral positions based in nine working groups – eight in biology and one in chemistry. Each research group will conduct research on a different organism or cells from other organisms so that we can capture and decipher the basic principles and reaction pathways in the formation of stress resistance across the biological spectrum, from algae to humans.”
– Prof. Dr. Johannes Herrmann
Officially, the Research Training Group will begin its research work next January. Nine other doctoral students who are also involved in the research will be able to benefit from the accompanying training program, which includes workshops, seminars, etc. The program will be coordinated by Dr. rer. nat. Gabriele Amoroso, who will take care of the scientific and non-scientific needs of the PhD students.
“We are delighted that the DFG is investing in our promotion of young scientists and thus in our future with this new research training group,” says Prof. Dr. Werner Thiel, Vice President for Research and Technology at TUK. “I would like to take this opportunity to congratulate all those involved! It should be emphasized that the program combines the research expertise of nine working groups and thus gives more visibility to our interdisciplinary research achievements in the natural sciences. Last but not least, it follows on almost seamlessly from a Research Training Group that was based in biology and was completed after nine years of funding. This means we can now continue the success story with a new research topic.”
Congratulations also come from the Rhineland-Palatinate Ministry of Science and Health. “I congratulate all the scientists involved in the initiative on this success,” said Science Minister Clemens Hoch. “The acquisition of a new research training group is an excellent demonstration of the research strength and the training of young scientists at the TU Kaiserslautern. TUK has successfully expanded its focus on membrane and systems biology in recent years, in part by taking advantage of the state’s research initiative. The new research training group will further strengthen the profile of the Kaiserslautern site.”
From the research work, the participants hope to gain a fundamental understanding of stress resistance at the molecular level. In this way, the findings from the Research Training Group could, for example, contribute to keeping people and animals healthy longer in old age or to making crops resistant to drought.
The Research Training Group is affiliated with the “BioComp – Complex Data Analysis in Life Sciences and Biotechnology” profile area, which is funded at the TUK as part of the state’s research initiative. This has enabled essential preparatory research work in recent years.
Negative influence by CO2 on important plankton group
The most important producers of plant biomass in the ocean are diatoms. Because they rely on silica rather than calcium carbonate to build their shells, they were previously considered winners of ocean acidification – a chemical change in seawater caused by the uptake of CO2 that makes calcification more difficult. In a study published today in the journal Nature, scientists at GEOMAR Helmholtz Centre for Ocean Research Kiel show that diatoms, which belong to the plankton, are also affected. Analysis suggests that increasing acidification could drastically reduce populations of diatoms.
While calcifying organisms in particular struggle to form their shells and skeletons in more acidic seawater, diatoms (diatoms) were previously thought to be less vulnerable to the effects of ocean acidification – a chemical change triggered by the uptake of carbon dioxide (CO2). The globally widespread tiny diatoms use silica, a compound of silicon, oxygen and hydrogen, as a building material for their shells. That diatoms are nevertheless threatened has now been demonstrated for the first time by researchers from GEOMAR Helmholtz Centre for Ocean Research Kiel, the Institute of Geological and Nuclear Sciences New Zealand and the University of Tasmania in a study published in the journal Nature. For their study, they linked an overarching analysis of various data sources with Earth system modeling. The findings provide a new assessment of the global impact of ocean acidification.
As a result of ocean acidification, the silicon shells of diatoms dissolve more slowly. This is not an advantage – because it causes diatoms to sink to deeper water layers than before before they chemically dissolve and are converted back to silica. Consequently, the nutrient is increasingly withdrawn from the global cycle and thus becomes scarcer in the light-flooded surface layer, where it is needed to form new shells. This causes a decline in diatoms, the scientists:in their current publication. Diatoms contribute 40 percent of the production of plant biomass in the ocean and are the basis of many marine food webs. They are also the main driver of the biological carbon pump that transports CO2 to the deep ocean for long-term storage.
“Using an overarching analysis of field experiments and observational data, we wanted to determine how ocean acidification affects diatoms on a global scale. Our current understanding of ecological effects of ocean change is largely based on small-scale experiments, i.e., from a particular place at a particular time. These findings can be deceptive if the complexity of the Earth system is not taken into account. Our study uses diatoms as an example to show how small-scale effects can lead to ocean-wide changes with unforeseen and far-reaching consequences for marine ecosystems and matter cycles. Since diatoms are one of the most important plankton groups in the ocean, their decline could lead to a significant shift in the marine food web or even a change for the ocean as a carbon sink.”
– Dr. Jan Taucher, marine biologist
The meta-analysis examined data from five mesocosm studies from 2010 to 2014, from different ocean regions, from Arctic to subtropical waters. Mesocosms are a type of large-volume, oversized test tube in the ocean, with a capacity of tens of thousands of liters, in which changes in environmental conditions in a closed but otherwise natural ecosystem can be studied. For this purpose, the water enclosed in the mesocosms was enriched in carbon dioxide to correspond to future scenarios with moderate to high increases in atmospheric CO2 levels. For the present study, the chemical composition of organic material from sediment traps was evaluated as it sank through the water contained in the experimental containers over the course of the experiments, which lasted several weeks. Combined with measurements from the water column, an accurate picture of biogeochemical processes within the ecosystem emerged.
The findings obtained from the mesocosm studies could be confirmed using global observational data from the open ocean. They show – in line with the results of the analysis – a lower dissolution of the silicon shells at higher seawater acidity. The resulting data sets were used to run simulations in an Earth system model to assess the ocean-wide consequences of the observed trends.
“Already by the end of this century, we expect a loss of up to ten percent of diatoms. That’s immense considering how important they are to life in the ocean and to the climate system,” Dr. Taucher continued. “However, it is important to think beyond 2100. Climate change will not stop abruptly, and global effects in particular take some time to become clearly visible. Depending on the amount of emissions, our model in the study predicts a loss of up to 27 percent silica in surface waters and an ocean-wide decline in diatoms of up to 26 percent by 2200 – more than a quarter of the current population.”
This finding of the study is in sharp contrast to the current state of ocean research, which sees calcifying organisms as losers and diatoms as profiteers from ocean acidification. Professor Ulf Riebesell, marine biologist at GEOMAR and head of the mesocosm experiments adds: “This study once again highlights the complexity of the Earth system and the associated difficulty in predicting the consequences of man-made climate change in its entirety. Surprises of this kind remind us again and again of the incalculable risks we run if we do not counteract climate change swiftly and decisively.”
Solutions for energy recovery from wastewater and organic waste
From May 30 to June 3, the sales team of biogas specialist Weltec Biopower will be available in Hall A4, Stand 217, to answer all questions relating to the construction and retrofitting of anaerobic energy plants: The range includes proven processes from the field of biogas technology. The high savings potential of these processes is demonstrated by the modernization of the municipal wastewater treatment plant in Bückeburg, Germany, which serves 33,000 inhabitants. Since Weltec Biopower switched to anaerobic sludge stabilization in 2021, operation of the plant at full load has become significantly more economical.
As general contractor, the company was responsible for the construction of the wastewater treatment system at the municipal sewage treatment plant. In addition to the earthworks, the construction of the foundation and the electrical cabling, the work included the construction of a new static sludge thickener, a machine room for the combined heat and power plant, the control and pumping station, and a stainless steel digester with a gas storage roof. Thanks to anaerobic wastewater treatment, the sludge volume has dropped by 35 percent, resulting in a significant reduction in transport and disposal costs. In addition, the digester gas produced can now generate around 465,000 kWh of electricity at full load. This allows the operator to meet about 40 percent of its electricity needs and save two-thirds of its electricity costs.
“In view of the new greenhouse gas reduction targets and the sharp rise in energy prices, an anaerobic stage is an economically attractive solution for wastewater treatment plant operators, which also benefits from public subsidies. Ultimately, the combination of wastewater treatment, power and heat generation, and climate protection enables more efficient operation, especially for small and medium-sized wastewater treatment plants.”
– Jens Albartus, Managing Director
How these goals can be achieved with organic waste is demonstrated by a WELTEC plant in Piddlehinton, southwest England. Here, a mix of food waste, expired food from supermarkets and organic waste is fed to the biogas plant. In addition to the substrate mix, the technical approach is also special. Before feeding and shredding, a de-packaging machine separates the food from the packaging.
Another efficiency bonus: The waste heat from the cogeneration plant is sold to a nearby feed producer, which also uses most of the electricity. The biogas plant operator feeds the excess electricity directly into the power grid, generating further revenue. The digestate from the process meets the requirements of the British industry standard PAS-100, so local farmers can use it as fertilizer.
Following a capacity expansion in 2014 from 20,000 t of substrate input per year to 30,000 t, the Group installed an additional digester and storage tank, as well as GasMix blending systems and a separation unit. A plant with this equipment would also support the conversion to biomethane production.
Therapeutics and bioinsecticides: production by spider venom
The venom of a single spider can contain up to 3000 components. The components, mostly peptides, can be used to develop promising active ingredient candidates for the treatment of diseases. Spider venom can also be used in pest control – as a biological pesticide. A team of researchers from the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Justus Liebig University Giessen is focusing on native spiders and their venom mix, which have received little attention to date. The research results on the biology of the toxins – especially on the venom of the wasp spider – have been published in scientific journals.
Spiders make many people uncomfortable, and some are even afraid of the eight-legged creatures. At the Fraunhofer Institute for Molecular Biology and Applied Ecology IME in Giessen, however, they are welcome. Here, biochemist Dr. Tim Lüddecke and his team are conducting research on spider toxins.
“Spider toxins are a largely untapped resource, this is partly due to the sheer diversity – some 50,000 species are known. There is a lot of potential in spider venom for medicine, for example in researching disease mechanisms.”
– Dr. Tim Lüddecke, head of the new “Animal Venomics” research group
For example, it is possible to study in the laboratory how individual toxins act on pain receptors of nerve cells. The venom cocktail of the Australian funnel web spider is particularly promising. It is assumed that it can be used to treat neuronal damage after strokes and to make hearts for organ transplants last longer. Other drug candidates are of interest for use as antibiotics or painkillers. “This is a very young field of research. The substances have been discovered and described, but they are not yet in the preclinical stage,” Lüddecke said. Pesticide research is a different story. Spiders stun insects with their venom and then eat them. Because the toxins are very effective against insects, they provide a good basis for biopesticides; they are suitable for crop pest control.
Research to date has focused on the toxins of the very large or potentially dangerous species that live in the tropics. The native, small and harmless spiders have not been in focus. “Most spiders in Central Europe are no more than two centimeters in size, and their venom levels were not sufficient for experiments. But now we have precise analytical methods to study even the small amounts of the previously neglected majority of spiders,” explains Lüddecke. The working group at the Giessen Bioresources branch of the Fraunhofer IME is devoting itself to these species as part of a research project. In the process, they are collaborating with research teams from the Justus Liebig University in Giessen, among others. The work is funded by the LOEWE Center for Translational Biodiversity Genomics (LOEWE-TBG) in Frankfurt am Main.
The scientists are paying particular attention to the wasp spider (Argiope bruennichi), which owes its name to its striking wasp-like coloration. They have succeeded in decoding its venom, identifying numerous novel biomolecules. The research findings were published in the journal Biomolecules.
New biomolecules from wasp spider venom
Spider venoms are highly complex, they can contain up to a maximum of 3000 components. The venom of the wasp spider, on the other hand, contains only about 53 biomolecules. It is heavily dominated by high-molecular-weight components, including so-called CAP proteins and other enzymes. As in other spider venoms, knottins are present – but these make up only a small part of the total mixture.
Knottins represent a group of neurotoxic peptides that are robust to chemical, enzymatic, and thermal degradation due to their nodal structure. One could therefore administer these molecules orally as a component of drugs without digesting them in the gastrointestinal tract. They can therefore exert their effects very well, which is why they offer great potential for medicine. In addition, knottins bind specifically to ion channels. “The more specifically a molecule docks onto its target molecule, attacking only a single type of ion channel, the fewer side effects it triggers,” explains Lüddecke. Moreover, even in small amounts, the knottins affect the activity of the ion channels, i.e., they are effective at low concentrations. As a result, derived drugs can be administered in low doses. The combination of these properties is what makes spider venoms so interesting for science.
The project partners also discovered molecules in the wasp spider’s venom that are similar in structure to neuropeptides, which are responsible for transporting information between nerve cells. “We have found novel families of neuropeptides that we have not previously seen in other spiders. We suspect that the wasp spider uses them to attack the nervous system of insects. It has been known for some time that neuropeptides in the animal kingdom are frequently converted into toxins in the course of evolution,” says the researcher.
Replicating toxins in the lab
Since the toxin yield is low in small spiders, the researchers extract the toxin glands and sequence the mRNA from them. Based on the gene structure, the toxins can be decoded. The venom profile of the wasp spider is now available in its entirety, and the next step is to produce the relevant components. For this, the gene sequence is incorporated into a bacterial cell using biotechnology, which then produces the toxin. “We are building quasi genetically modified bacteria that produce the toxin on a large scale.” Lüddecke and his team have been able to mass produce the main component of the wasp spider toxin, the CAP protein. The first functional studies will start soon.
Venom of male and female spiders differs
In another review paper, the biochemist, in cooperation with colleagues at the Justus Liebig University of Giessen and researchers at the Australian University of the Sunshine Coast, was able to deduce that spider venoms are very dynamic and that many influences shape their composition and functionality. “The dynamics of spider venom have been completely underestimated. The biochemical repertoire is critically influenced by life stage, habitat, and especially sex. Even the venom cocktail of juveniles and adults is not necessarily identical. It is rather the interaction of the many components that makes spider venom so effective than the effect of a single toxin. Through their interactions, the components increase their effectiveness,” the researcher sums up.