Press releases

 

May 17 2021
15:23

How novel therapeutics provide insight into bacteria membranes 

In slow motion against antibiotic resistance

Whether bacteria are resistant to antibiotics is often decided at the cell membrane. This is where antibiotics can be blocked on their way into the cell interior or catapulted from the inside to the outside. Macrocyclic peptides, a novel class of antibiotics, bioactive cytotoxins and inhibitors, shed light on how this transport process occurs at the membrane, how it is influenced and how it can be used to circumvent the resistance of a malignantly transformed cell. The research results, which were developed under the direction of Professor Robert Tampé (Goethe University) and Professor Hiroaki Suga (University of Tokyo), have been published in the renowned journal eLife (20-02-2021-RA-eLife-67732). 

FRANKFURT. There are currently only a few synthetic agents that bind to and block the widespread membrane transport proteins, ATP-binding cassette transporters (ABC). Scientists at Goethe University and the University of Tokyo identified four of these macrocyclic peptides as models for a novel generation of active substances. They used methods for which the scientists involved are considered world leaders.

Thanks to deep sequencing, an extremely fast and efficient read-out procedure, the desired macrocyclic peptides could be filtered out of a "library" of macrocyclic peptides comprising trillions of variants (1 with 12 zeroes) - a number that exceeds the number of stars in the Milky Way. The fact that such an enormous amount exists at all is related to a novel procedure: By reprogramming the genetic code, amino acids can be used specifically as active components that are not otherwise used in the cell. In particular, their circular, closed structure distinguishes them from natural proteins. "Because these therapeutics are cyclic, they break down less rapidly in the cell," explains Robert Tampé, Director of the Institute of Biochemistry at Goethe University. "In addition, the ring-shaped active substances are restricted in their spatial structure, so they bind to the target molecule without major rearrangements." A third distinguishing feature makes macrocyclic peptides particularly attractive for scientists: When the active substances are produced, their building instructions are supplied as a "barcode". If certain therapeutics are selected from among a trillion synthetically produced ones, they carry their "name tags" with them, so to speak.

So what role do synthetic therapeutics play in antibiotic resistance in bacteria or multidrug resistance in tumour cells? What happens when they encounter the ATP-driven transport molecule that is responsible for resistance by carrying the chemotherapeutic agents out of the cell? In a nutshell: The drugs block the transporter by binding to it. This can happen at the beginning or at the end of a transport process, when the transporter is in a resting state. However, since the scientists can slow down the transport process so that it is carried out in slow motion, they can identify the agents that "enter" in the middle of the transport process and "hold" the membrane protein in its respective position. In this way, the researchers gain an insight into the choreography of the transport process as if through the images of a film strip.

These insights have already led to a "paradigm shift" in science, as Tampé explains: "Until now, we have assumed that ATP hydrolysis (note: an energy-releasing splitting process) provides the energy for transport through the membrane. However, this is only indirectly the case. It is the event of the binding of the ATP molecule that pushes substances out of the cell. The energy of hydrolysis, on the other hand, is used to return the ABC transporter to its initial state." The research groups at Goethe University and the University of Tokyo are convinced that these and other insights into membrane processes will point to the development of future medicines.

Basic research on cellular membranes and membrane proteins already has a long tradition in Frankfurt. Robert Tampé elucidated essential mechanisms of ATP-driven transport proteins and cellular machinery of adaptive immune response and quality control, which together with this new publication can provide approaches for applied drug research. Tampé was head of the Collaborative Research Centre "Transport and Communication across Biological Membranes" (SFB 807) which expired at the end of 2020. Meanwhile the concept for a new research centre on highly dynamic processes related to protein networks and machineries in cellular membranes is already under development. In the long term, the research results should reveal new possibilities for the therapy of molecular diseases, infections and cancer.

Publication:
Erich Stefan, Richard Obexer, Susanne Hofmann, Khanh Vu Huu, Yichao Huang, Nina Morgner, Hiroaki Suga, Robert Tampé: “De novo macrocyclic peptides dissect energy coupling of a heterodimeric ABC transporter by multimode allosteric inhibition“ (20-02-2021-RA-eLife-67732)

Stefan, Hofmann, and Tampé at the Institute of Biochemistry at Goethe University, Vu Huu and Morgner at the Institute for Physical and Theoretical Chemistry at Goethe University, and Obexer, Huang and Suga at the Department of Chemistry, University of Tokyo.

Images for download: www.uni-frankfurt.de/101026220
(Graphic: Robert Tampé, Institute for Biochemistry, Biocentre, Goethe University Frankfurt)
Caption: Synthetic therapeutics for antibiotic resistance in bacteria or multidrug resistance in tumour cells can block ATP-driven transport proteins that carries chemotherapeutics out of the cell 

Further information
Professor Robert Tampé
Institute of Biochemistry, Biocentre
Goethe University Frankfurt
tampe@em.uni-frankfurt.de

Professor Hiroaki Suga
Department of Chemistry
Graduate School of Science
The University of Tokyo
hsuga@chem.s.u-tokyo.ac.jp


Editor: Pia Barth, Public Relations, PR & Communication Department, Tel: -49 (0) 69 798-12481, Fax: +49 (0) 69 798-763 12531, p.barth@em.uni-frankfurt.de

 

May 10 2021
14:53

Remdesivir metabolite GS-441524 binds to the SARS-CoV-2 protein nsP3 – potential for drug development to combat numerous other viruses 

SARS-CoV-2 Research: Second possible effective mechanism of remdesivir discovered

When a cell is infected, SARS-CoV-2 not only causes the host cell to produce new virus particles. The virus also suppresses host cell defence mechanisms. The virus protein nsP3 plays a central role in this. Using structural analyses, researchers at Goethe University in cooperation with the Swiss Paul Scherrer Institute have now discovered that a decomposition product of the virostatic agent remdesivir binds to nsP3. This points to a further, previously unknown effective mechanism of remdesivir which may be important for the development of new drugs to combat SARS-CoV-2 and other RNA viruses.

FRANKFURT. The virostatic agent remdesivir was developed to disrupt an important step in the propagation of RNA viruses, to which SARS-CoV-2 also belongs: the reproduction of the virus's own genetic material. This is present as RNA matrices with which the host cell directly produces virus proteins. To accelerate the production of its own proteins, however, RNA viruses cause the RNA matrices to be copied. To do so, they use a specific protein of their own (an RNA polymerase), which is blocked by remdesivir. Strictly speaking, remdesivir does not do this itself, but rather a substance that is synthesized from remdesivir in five steps when remdesivir penetrates a cell.

In the second of these five steps, an intermediate is formed from remdesivir, a substance with the somewhat unwieldy name GS-441524 (in scientific terms: a remdesivir metabolite). GS-441524 is a virostatic agent as well. As the scientists in the group headed by Professor Stefan Knapp from the Institute for Pharmaceutical Chemistry at Goethe University Frankfurt have discovered, GS-441524 targets a SARS-CoV-2 protein called nsP3. nsP3 is a multifunctional protein, whose tasks include suppressing the host cell's defence response. The host cell is not helpless in the face of a virus attack, but activates inflammatory mechanisms, among other things, to summon the aid of the cell's endogenous immune system. nsP3 helps the viruses suppress the cell's calls for help.

Professor Stefan Knapp explains: “GS-441525 inhibits the activities of an nsP3 domain which is important for the reproduction of viruses, and which communicates with human cellular defence systems. Our structural analysis shows how this inhibition functions, allowing us to lay an important foundation for the development of new and more potent antiviral drugs – effective not only against SARS-CoV-2. The target structure of GS-441524 is very similar in other coronaviruses, for example SARS-CoV and MERS-CoV, as well in a series of alphaviruses, such as the chikungunya virus. For this reason, the development of such medicines could also help prepare for future virus pandemics."

Publication: Xiaomin Ni, Martin Schröder, Vincent Olieric, May E. Sharpe, Victor Hernandez-Olmos, Ewgenij Proschak, Daniel Merk, Stefan Knapp, Apirat Chaikuad: Structural Insights into Plasticity and Discovery of Remdesivir Metabolite GS-441524 Binding in SARS-CoV‑2 Macrodomain. ACS Med. Chem. Lett. 2021, 12, 603−609 https://pubs.acs.org/doi/10.1021/acsmedchemlett.0c00684

Further information
Professor Stefan Knapp
Institute for Pharmaceutical Chemistry and
Buchmann Institute for Molecular Life Sciences
Goethe University Frankfurt
Tel. +49 69 798-29871
knapp@pharmchem.uni-frankfurt.de
https://www.uni-frankfurt.de/53483664/Knapp


Editor: Dr. Markus Bernards, Science Editor, PR & Communication Department, Tel: -49 (0) 69 798-12498, Fax: +49 (0) 69 798-763 12531, E-Mail: bernards@em.uni-frankfurt.de

 

May 10 2021
14:09

DFG Research Training Group “Configurations of film“ at Goethe University can continue its work

Moving pictures on the move

What happens when film leaves the cinema and becomes available everywhere – out and about on mobile devices, or in the living room at home? The Graduiertenkolleg (Research Training Group) “Configurations of Film" at Goethe University has been researching the current transformation of film and cinema culture since 2017. The German Research Foundation has now given the project the green light to continue.


FRANKFURT. “We are happy that the German Research Foundation's has kept their trust in us so that we can continue to our work in the Kolleg," says Vinzenz Hediger, professor for film studies and speaker of the Kolleg. In individual studies that include the participation of the disciplines of philosophy, literary studies and theatre studies, the Kolleg examines a fundamental problem in film studies: the transformation of its objects through the progressive digitalisation of the production, distribution and perception of moving images. "The medium of the moving image, which was standardised for global distribution in an international agreement as early as 1905, has always been a medium in motion," says Hediger. "With digitalisation, however, cinema itself as the privileged place of film is now being called into question, with far-reaching consequences for the aesthetics, as well as for the social impact and significance of films and other moving image formats."


The Graduiertenkolleg at the Institute for Theatre, Film and Media Studies started in 2017 with twelve doctoral candidates and two post-docs. Currently, the second group with a another twelve young sceintists from Germany, India and Nigeria is already at work. In close collaboration with the two postdocs of the Kolleg, they deal with topics as diverse as the interpenetration of film and video and computer games, the afterlife of Rainer Werner Fassbinder's work and reputation, the role of textiles in Nigerian historical films or the digital rediscovery of popular Bengali cinema of the 1950s and 1960s.


The Graduiertenkolleg is run in cooperation with the Universities of Mainz and Marburg and the University for Art and Design in Offenbach. The Kolleg builds on three Master's programmes at Goethe University as well as collaborations among the applicant researchers. It utilises the potential of Frankfurt as a location, where the university library and the German National Library have literature holdings of European standing and important non-university partners are available in the form of the German Film Institute, the Murnau Foundation and the Max Planck Institute for Empirical Aesthetics. The Kolleg is developing an international reputation through its cooperation with Yale University and Concordia University.


The Kolleg attracted attention among experts in autumn 2020 with the publication "Pandemic Media. Preliminary Notes towards an Inventory", in which 37 authors from the Kolleg and its international network reflect on global media culture under pandemic conditions. The book is available in open access at the academic publisher meson press (https://meson.press/books/pandemic-media/).


Further information:
Professor Vinzenz Hediger

Graduiertenkolleg „Configurations of Film“

Institute for Theatre, Film and Media Studies
hediger@tfm.uni-frankfurt.de


Editor: Dr. Anke Sauter, Science and Humanities Editor, International Communication, PR & Communication Department, Phone: +49 69 798-13066, Fax  +49(0)69 798-761 12531, sauter@pvw.uni-frankfurt.de.

 

May 10 2021
08:55

80 percent of all SARS-CoV-2 proteins produced in the laboratory – protocols available for worldwide research - Goethe University Frankfurt forms the hub of research network from 17 countries

SARS-CoV-2 research accelerator: worldwide network headed by Goethe University develops protocols for laboratories

For the development of drugs or vaccines against COVID-19, research needs virus proteins of high purity. For most of the SARS-CoV-2 proteins, scientists at Goethe University Frankfurt and a total of 36 partner laboratories have now developed protocols that enable the production of several milligrams of each of these proteins with high purity, and allow the determination of the three-dimensional protein structures. The laboratory protocols and the required genetic tools are freely accessible to researchers all over the world.

FRANKFURT. When the SARS-CoV-2 virus mutates, this initially only means that there is a change in its genetic blueprint. The mutation may lead, for example, to an amino acid being exchanged at a particular site in a viral protein. In order to quickly assess the effect of this change, a three-dimensional image of the viral protein is extremely helpful. This is because it shows whether the switch in amino acid has consequences for the function of the protein - or for the interaction with a potential drug or antibody.

Researchers at Goethe University Frankfurt and TU Darmstadt began networking internationally from the very start of the pandemic. Their goal: to describe the three-dimensional structures of SARS-CoV-2 molecules using nuclear magnetic resonance spectroscopy (NMR). In NMR spectroscopy, molecules are first labelled with special types of atoms (isotopes) and then exposed to a strong magnetic field. NMR can then be used to look in detail and with high throughput at how potentially active compounds bind to viral proteins. This is done at the Centre for Biomolecular Magnetic Resonance (BMRZ) at Goethe University and other locations. However, the basic prerequisite is to produce large quantities of the proteins in high purity and stability, and with their correct folding, for the large amount of tests.

The network, coordinated by Professor Harald Schwalbe from the Institute of Organic Chemistry and Chemical Biology at Goethe University, spans the globe. The elaboration of laboratory protocols for the production of proteins is already the second milestone. In addition to proteins, the virus consists of RNA, and the consortium already made all important RNA fragments of SARS-CoV-2 accessible last year. With the expertise of 129 colleagues, it has now been possible to produce and purify 23 of the total of almost 30 proteins of SARS-CoV-2 completely or as relevant fragments "in the test tube", and in large amounts.

For this purpose, the genetic information for these proteins was incorporated into small, ring-shaped pieces of DNA (plasmids). These plasmids were then introduced into bacteria for protein production. Some special proteins were also produced in cell-free systems. Whether these proteins were still correctly folded after their isolation and enrichment was confirmed, among other things, by NMR spectroscopy.

Dr Martin Hengesbach from the Institute of Organic Chemistry and Chemical Biology at Goethe University explains: "We have isolated functional units of the SARS-CoV-2 proteins in such a way that their structure, function and interactions can now be characterised by ourselves and others. In doing so, our large consortium provides working protocols that will allow laboratories around the world to work quickly and reproducibly on SARS-CoV-2 proteins and also the mutants to come. Distributing this work from the beginning was one of our most important priorities. In addition to the protocols, we are also making the plasmids freely available."

Dr Andreas Schlundt from the Institute for Molecular Biosciences at Goethe University says: "With our work, we are speeding up the global search for active agents: Scientific laboratories equipped for this work do not have to first spend several months establishing and optimising systems for the production and investigation of SARS-CoV-2 proteins, but can now start their research work within two weeks thanks to our elaborated protocols. Given the numerous mutations of SARS-CoV-2 to come, it is particularly important to have access to reliable, rapid and well-established methods for studying the virus in the laboratory. This will, for example, also facilitate research on the so-called helper proteins of SARS-CoV-2, which have remained under-investigated, but which also play a role in the occurrence of mutations."

In the meantime, the work in the NMR consortium continues: Currently, the researchers are working hard to find out whether viral proteins can bind to potential drugs.

The research work was funded by the German Research Foundation and the Goethe Coronavirus Fund. The high logistical effort and constant communication of research results was supported by Signals, a spin-off company of Goethe University.

Publication: Nadide Altincekic, Sophie Marianne Korn, Nusrat Shahin Qureshi, Marie Dujardin, Martí Ninot-Pedrosa et. al. Large-scale recombinant production of the SARS-CoV-2 proteome for high-throughput and structural biology applications. Frontiers in Molecular Biosciences. https://doi.org/10.3389/fmolb.2021.653148

Additional information: Folding of SARS-CoV2 genome reveals drug targets – and preparation for “SARS-CoV3" https://tinygu.de/IcOo2

Images may be downloaded here: www.uni-frankfurt.de/100668377

Caption: Scientists Martin Hengesbach (left) und Andreas Schlundt at the nuclear magnetic resonance (NMR) spectrometre at Goethe-University Frankfurt, Germany. Photo: Uwe Dettmar for Goethe-University Frankfurt, Germany

The COVID-19 NMR Consortium:
https://covid19-nmr.de/

Scientific contacts at Goethe University Frankfurt:
Dr Andreas Schlundt
Emmy Noether Junior Group Leader
Institute for Molecular Biosciences
Goethe University Frankfurt
Tel.: +49 69 798-29699
schlundt@bio.uni-frankfurt.de

Dr Martin Hengesbach
Junior Group Leader
Goethe University Frankfurt
Institute for Organic Chemistry and Chemical Biology
SFB 902 “Molecular Principles of RNA-based Regulation“
Tel.: +49 69 798-29130
hengesbach@nmr.uni-frankfurt.de

Partners:

Brazil

  • National Center of Nuclear Magnetic Resonance (CNRMN, CENABIO), Federal University of Rio de Janeiro, Brazil
  • Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Brazil
  • Multidisciplinary Center for Research in Biology (NUMPEX), Campus Duque de Caxias, Federal University of Rio de Janeiro, Duque de Caxias, Brazil
  • Institute of Chemistry, Federal University of Rio de Janeiro, Brazil
  • Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, São Paulo State University (UNESP), São José do Rio Preto, Brazil
  • Laboratory of Toxicology, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil

France

  • Molecular Microbiology and Structural Biochemistry (MMSB), UMR 5086, CNRS/Lyon University, France
  • Université Grenoble Alpes, CNRS, CEA, IBS, Grenoble, France

Germany

  • Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt, Germany
  • Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Germany
  • Institute for Molecular Biosciences, Goethe University Frankfurt, Germany
  • Institute for Biochemistry, Goethe University Frankfurt, Germany
  • Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Germany
  • Institute of Biophysical Chemistry, Goethe University Frankfurt, Germany
  • BMWZ and Institute of Organic Chemistry, Leibniz University Hannover, Germany
  • Group of NMR-based Structural Chemistry, Helmholtz Centre for Infection Research, Braunschweig, Germany
  • Structural Genomics Consortium, Buchmann Institute for Molecular Life Sciences (BMLS), Germany
  • Signals GmbH & Co. KG, Frankfurt am Main, Germany
  • Leibniz Institute on Aging – Fritz Lipmann Institute (FLI), Jena, Germany
  • IBG-4, Karlsruhe Institute of Technology, Karlsruhe, Germany
  • Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
  • Institute of Biochemistry and Biotechnology, Charles Tanford Protein Centre, Martin Luther University Halle-Wittenberg, Halle/Saale, Germany.

Greece

  • Department of Pharmacy, University of Patras, Greece

Italy

  • Structural Biology and Biophysics Unit, Fondazione Ri.MED, Palermo, Italy
  • Magnetic Resonance Centre (CERM), University of Florence, Sesto Fiorentino, Italy
  • Department of Chemistry “Ugo Schiff", University of Florence, Sesto Fiorentino, Italy

Latvia

  • Latvian Biomedical Research and Study Centre, Riga, Latvia
  • Latvian Institute of Organic Synthesis, Riga, Latvia

Switzerland

  • Swiss Federal Institute of Technology, Laboratory of Physical Chemistry, ETH Zurich, Zurich, Switzerland

Spain

  • "Rocasolano" Institute for Physical Chemistry (IQFR), Spanish National Research Council (CSIC), Serrano, Spain

USA

  • Institute for Molecular Virology, University of Wisconsin-Madison, WI, United States
  • Department of Chemistry, University of California, Irvine, United States
  • Laboratory of Chemical Physics, National Institute of Diabetes and Digestive Kidney Diseases, National Institute of Health, United States
  • Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH, United States
  • Department of Molecular Biology and Biochemistry, University of California, Irvine, California, United States
  • Department of Molecular Biology and Biophysics, UC 72 onn Health, Farmington, CT, United States


Editor: Dr. Markus Bernards, Science Editor, PR & Communication Department, Tel: -49 (0) 69 798-12498, Fax: +49 (0) 69 798-763 12531, E-Mail: bernards@em.uni-frankfurt.de

 

Apr 23 2021
11:15

Goethe University researchers investigate oxidative stress in mice

How oxygen radicals protect against cancer

Oxygen radicals in the body are generally considered dangerous because they can trigger something called oxidative stress, which is associated with the development of many chronic diseases such as cancer and cardiovascular disease. In studies on mice, scientists at Goethe University Frankfurt have now discovered how oxygen radicals, conversely, can also reduce the risk of cancer and mitigate damage to the hereditary molecule DNA. (PNAS, DOI 10.1073/pnas.2020152118).

FRANKFURT. Originally, oxygen radicals - reactive oxygen species, or ROS for short - were considered to be exclusively harmful in the body. They are produced, for example, by smoking or UV radiation. Because of their high reactivity, they can damage many important molecules in cells, including the hereditary molecule DNA. As a result, there is a risk of inflammatory reactions and the degeneration of affected cells into cancer cells.

Because of their damaging effect, however, ROS are also deliberately produced by the body, for example by immune or lung epithelial cells, which destroy invading bacteria and viruses with ROS. This requires relatively high ROS concentrations. In low concentrations, on the other hand, ROS play an important role as signalling molecules. For these tasks, ROS are specifically produced by a whole group of enzymes. One representative of this group of enzymes is Nox4, which continuously produces small amounts of H2O2. Nox4 is found in almost all body cells, where its product H2O2 maintains a large number of specialised signaling functions, contributing, for example, to the inhibition of inflammatory reactions.

Researchers at Goethe University Frankfurt, led by Professor Katrin Schröder, have now discovered that by producing H2O2, Nox4 can even prevent the development of cancer. They examined mice that were unable to produce Nox4 due to a genetic modification. When these mice were exposed to a carcinogenic environmental toxin (cancerogen), the probability that they would develop a tumour doubled. Since the mice suffered from very different types of tumours such as skin sarcomas and colon carcinomas, the researchers suspected that Nox4 has a fundamental influence on cellular health.

Molecular investigations showed that the H2O2 formed by Nox4 keeps a cascade going that prevents certain important signalling proteins (phosphatases) from entering the cell nucleus. If Nox4 and consequently H2O2 are absent, those signalling proteins migrate into the cell nucleus and as a consequence, severe DNA damage is hardly recognised.

Severe DNA damage - e.g. double strand breaks - occurs somewhere in the body every day. Cells react very sensitively to such DNA damage, setting a whole repertoire of repair enzymes in motion. If this does not help, the cell activates its cell death programme - a precautionary measure of the body against cancer. When such damage goes unrecognised, as occurs in the absence of Nox4, it spurs cancer formation.

Prof. Katrin Schröder explains the research results: "If Nox4 is missing and there is therefore no H2O2, the cells no longer recognise DNA damage. Mutations accumulate and damaged cells continue to multiply. If an environmental toxin is added that massively damages the DNA, the damage is no longer recognised and repaired. The affected cells are not eliminated either, but multiply, sometimes very quickly and uncontrollably, which eventually leads to the development of tumours. A small amount of H2O2 thus maintains an internal balance in the cell that protects the cells from degeneration."

Publication: Valeska Helfinger, Florian Freiherr von Gall, Nina Henke, Michael M. Kunze, Tobias Schmid, Flavia Rezende, Juliana Heidler, Ilka Wittig, Heinfried H. Radeke, Viola Marschall, Karen Anderson, Ajay M. Shah, Simone Fulda, Bernhard Brüne, Ralf P. Brandes, Katrin Schröder: Genetic deletion of Nox4 enhances cancerogen-induced formation of solid tumors. PNAS, https://doi.org/10.1073/pnas.2020152118

Further information
Professor Katrin Schröder
Institute for Cardiovascular Physiology
Faculty of Medicine
Goethe University Frankfurt
Phone +49(0)69-6301-83660
schroeder@vrc.uni-frankfurt.de
http://www.vrc.uni-frankfurt.de



Editor: Dr. Markus Bernards, Science Editor, PR & Communication Department, Tel: -49 (0) 69 798-12498, Fax: +49 (0) 69 798-763 12531, E-Mail: bernards@em.uni-frankfurt.de