Press releases – November 2018

 

Nov 29 2018
09:07

Significant increase in number of successful scientists in Clarivate Analytics ranking

Thirteen Goethe University researchers among most highly cited

FRANKFURT. Every year, a list is published of the top one percent of researchers worldwide, based on the frequency with which their work is cited by other scientists according to data from the “Web of Science”. The number of natural and medical scientists from Goethe University on the list increased from three to thirteen in the past year. 

Goethe University also stands out in comparison with other German universities: only Heidelberg University has one more researcher listed. The German research institution with the greatest number of highly cited researchers is the Max Planck Institute, which had 76 researchers on the list. A total of 256 researchers form German institutions made it on the list, which includes 6078 researchers in 22 different scientific disciplines. 

The most highly cited researchers at Goethe University are atmospheric researcher

Joachim Curtius, biochemist Ivan Dikic, biologist Stefanie Dimmeler, hydrologist Petra Döll, pharmacologist Jennifer Dressman, geographer Thomas Hickler, cardiologist Stefan Hohnloser, pharmacist Stefan Knapp, cancer researcher Sibylle Loibl, medical scientist Christoph Sarrazin, brain researcher Wolf Singer, physicist Ernst Stelzer, and medical scientist Stefan Zeisel.

“Web of science“ is a platform for researching academic literature. It indexes all scientific and reviewed publications, and also determines how frequently each publication is cited. It is operated by the company Clarivate Analytics.

Further information: Prof. Dr. Joachim Curtius, Institute for Geosciences, Riedberg Campus, Tel.: -49 69 798-40258, curtius@iau.uni-frankfurt.de.

List of highly cited researchers: https://hcr.clarivate.com/ 

 

Nov 29 2018
08:41

Award winner Alexander Vogel carries out research for better air quality

Searching for the sources of particulate matter

FRANKFURT. Particulate matter is a form of pollution whose sources are not all understood to this day. The very complex mixture is formed in the atmosphere from various gaseous precursor molecules. Identifying their sources and improving air quality is the goal of Alexander Vogel, Professor for Atmospheric Environmental Analytics at Goethe University. For his research projects, he received the Adolf Messer Foundation Award at a ceremony on 26th November. In honour of its 25th anniversary, the award amounts to € 50,000 this year. 

University President Professor Birgitta Wolff: “Congratulations to Alexander Vogel! He is doing research on an issue of global importance that affects us all, especially in metropolitan areas: particulate matter. His research can contribute to a better understanding of this threatening phenomenon and make the cities of the world healthier. We thank the Foundation for its tireless work on behalf of early career researchers at Goethe University. And we welcome the fact that the Foundation has addressed its historical responsibility in its recently published clarification on the role of its namesake Adolf Messer.” 

Hessian Minister for Education, Culture and the Arts Boris Rhein: „My warmest congratulations to Professor Alexander Vogel. His research is highly relevant – particulate matter threatens our health and is something we must understand and learn to combat. Excellent research, such as that done by Professor Vogel and many of his colleagues, requires excellent conditions. Now the government of the state of Hesse and the universities in Hesse have both signed the Higher Education Pact for the years 2016 to 2020, creating financial planning certainty for Hesse’s universities through 2020. The Higher Education Pact is a milestone for Hesse as a science location and guarantees Hesse’s universities € 9 million in financial resources for the next five years. That is the largest sum ever made available to Hesse’s universities.” 

Foundation Board Chair, Stefan Messer, stressed: “Every foundation should make it their job to support projects and ideas that are not adequately covered by basic government funding. This is the idea pursued by our non-profit foundation in its funding and recognition of scientists stand out due to their exceptional achievements. We are very happy that in 2018, innovation, scientific curiosity, and pioneering spirit have been recognized for the 25th time in this manner.” 

About the award winning project

According to estimates by the World Health Organisation, about 6.5 million people worldwide die prematurely due to air pollution, most of which can be attributed to particulate air pollution. Contrary to popular opinion, most particulate matter doesn’t enter the atmosphere straight from tailpipes or power plants, but is formed in the atmosphere itself out of gaseous precursor molecules. This secondary particulate matter consists of the tiniest particles with an average diameter in the nanometre-range. These can penetrate deep into the lung and even enter the blood via the alveoles.  An example for the formation of secondary particulate matter is the oxidation of nitrogen oxides from diesel engines: the resulting nitric acid molecules react with ammonia in the atmosphere to create ammonium nitrate.

The inorganic precursor molecules and their development to secondary particulate matter have been well investigated: nitrogen oxides from traffic and industry, sulphur dioxide from coal-burning power plants and ammonia from agriculture. But there are numerous organic molecules on top of this that also occur in nature, such as the terpenes emitted by spruce forests. Organic precursor molecules emitted by human activity in relation to the formation of secondary particulate matter is a highly topical research area. These precursor molecules and their interaction with inorganic trace gases have only been rudimentarily investigated to date. The clear identification of the products of these chemical reactions is made difficult by the fact that the molecules often have the same mass, although their structures are different.

While he was a postdoctoral fellow at the Paul Scherrer Institute in Switzerland, Alexander Vogel developed a method for creating a molecular fingerprint from atmospheric particular matter samples. By analysing them, he can determine the secondary formation mechanism. The molecular fingerprint of particulate matter samples from Los Angeles, for example, exhibits a high percentage of nitrogen-containing organic molecules. “This allows the assumption that a reduction in nitrogen oxide emissions would also lead to a reduction of organic particulate air pollution in urban areas,” Vogel explains.

However, to elucidate the formation mechanisms of individual substances, further analyses of atmospheric samples and specific laboratory experiments in which the formation of particulate matter is simulated are necessary. By comparing field measurements with experiments, Alexander Vogel can already assign a portion of the signals in the real samples to certain processes and precursor molecules. Of the remaining unknowns, at least the molecular formula can be determined, so that potential sources and formation mechanisms can be investigated in further laboratory tests.

Alexander Vogel will now set up the experimental method he developed at the Paul Scherrer Institute at Goethe University. Among other things, he requires a machine for high performance liquid chromatography, which thanks to the Adolf Messer Foundation can now be acquired. His research approach has been met with great interest among environmental science master degree students. The measurements are due to begin at the start of 2019. Applications for master’s and doctoral theses are already coming in.

The great relevance of this topic will also be emphasized in a symposium accompanying the award. With the title “Understanding particulate matter: A grand challenge of the 21st century?”, particulate matter measurement at the Frankfurt International Airport, smog in Chinese cities, and the health effects of particulate matter will be discussed.

Alexander Vogel, born in 1984, studied chemistry at Johannes Gutenberg-Universität Mainz. After receiving his Ph.D. (2014), research on the CLOUD experiment took him to the European Organization for Nuclear Research CERN by Geneva and the Paul Scherrer Institute in Villigen, Switzerland. He has been a tenure-track professor for atmospheric environmental analysis at Goethe University since January 2018.

Further information: Professor Alexander Vogel, Institute for Atmosphere and Environment, Faculty of Geosciences, Riedberg Campus, Tel.: +49 69 798-40225, vogel@iau.uni-frankfurt.de.

 

Nov 29 2018
08:27

The exchange of water between the North and South Atlantic became significantly larger fifty-nine million years ago

Scientists discover how the Atlantic Ocean became part of the global circulation at a climatic tipping point

A team of scientists, led by Dr Sietske Batenburg at the University of Oxford’s Department of Earth Sciences, in close collaboration with Goethe University and other German and UK institutions, have discovered that the exchange of water between the North and South Atlantic became significantly larger fifty-nine million years ago. 

The scientists made this discovery when they compared neodymium isotope signatures of deep sea sediment samples from both regions of the Atlantic. Their paper – ‘Major intensification of Atlantic overturning circulation at the onset of Paleogene greenhouse warmth’ – published today in Nature Communications, reveals that the more vigorous circulation together with an increase in atmospheric CO2 led to a climatic tipping point. With a resulting more even distribution of heat over the earth, a long-term cooling phase ended and the world headed into a new greenhouse period. 

Neodymium (Nd) isotopes are used as a tracer of water masses and their mixing. Surface waters acquire a Nd-isotope signature from surrounding land masses through rivers and wind-blown dust. When surface waters sink to form a deep-water mass, they carry their specific Nd-isotope signature with them. As a deep-water mass flows through the ocean and mixes with other water masses, its Nd-isotope signature is incorporated into sediments. Deep sea sediments are valuable archives of ocean circulation and past climates.

The story revealed in this paper begins at the end of the Cretaceous period (ending 66 million years ago), when the world was between two greenhouse states. Climate had been cooling for tens of millions of years since the peak hothouse conditions of the mid-Cretaceous, around 90 million years ago. Despite long-term cooling, temperatures and sea level at the end of the Cretaceous period were higher than at present day.

Dr Sietske Batenburg says: ‘Our study is the first to establish how and when a deep-water connection formed. At 59 million years ago, the Atlantic Ocean truly became part of the global thermohaline circulation, the flow that connects four of the five main oceans.’

The Atlantic Ocean was still young, and the North and South Atlantic basins were shallower and narrower than today. The equatorial gateway between South America and Africa only allowed a shallow, surface-water connection for much of the late Cretaceous period. Active volcanism formed underwater mountains and plateaus that blocked deep-water circulation. In the South Atlantic, the Walvis Ridge barrier formed above an active volcanic hotspot. This ridge was partially above sea level and formed a barrier for the flow of deep-water masses.

As the Atlantic Ocean continued to open, the oceanic crust cooled and subsided. Basins became deeper and wider, and submarine plateaus and ridges sank, along with the crust. At some point, deep water from the Southern Ocean was able to flow north across the Walvis Ridge and fill the deeper parts of the Atlantic basins.

From 59 million years ago onwards, Nd-isotope signatures from the North and South Atlantic were remarkably similar. This may indicate that one deep-water mass, likely originating from the south, made its way through the Atlantic Ocean and filled the basin from deep to intermediate depths. The enhanced deep water exchange, together with increasing atmospheric CO2, may have enabled a more efficient distribution of heat over the planet.

This study shows that to understand the role of ocean circulation in past greenhouse climates, it is important to understand the different roles of geography and climate.

The current rate of climate change by CO2 emissions from human activity by far surpasses the rate of warming during past greenhouse climates. Studying ocean circulation during the most recent greenhouse interval in the geologic past may provide clues as to how ocean circulation might develop in the future, and how heat will be distributed over the planet by ocean currents.

This research is the result of an international collaboration with the Goethe-University Frankfurt; the Ruprecht-Karls-University of Heidelberg; the GEOMAR Helmholtz Centre for Ocean Research Kiel; the Federal Institute for Geosciences and Natural Resources in Hannover; the Royal Holloway University of London and the University of Oxford.

The sediments for this study were all taken from long ocean drill cores. The International Ocean Discovery Program (IODP) coordinates scientific expeditions to drill the ocean floor to recover these sediments, and stores the sediment cores so that they are available to the whole scientific community.

Publication: S.J. Batenburg, S. Voigt, O. Friedrich, A.H. Osborne, A. Bornemann, T. Klein1, L. Pérez-Díaz und M. Frank: Major intensification of Atlantic overturning circulation at the onset of Paleogene greenhouse warmth, in: Nature Communications, DOI: 10.1038/s41467-018-07457-7

Images may be downloaded at: www.uni-frankfurt.de/74972308; Credit: Sietske Batenburg

Further information: Professor Silke Voigt, Institute for Geosciences, Geology, Riedberg Campus, Tel.: +49 69 798-40190, s.voigt@em.uni-frankfurt.de.

 

Nov 26 2018
11:41

Surprising discovery of a chimeric protein that combines both ion pump and ion channel

How does potassium enter cells?

FRANKFURT. For decades it was assumed that protein channels and protein pumps fulfilled completely different functions and worked independently of each other. Researchers at Goethe University Frankfurt and University Groningen have now elucidated the transport path of a protein complex that combines both mechanisms: it first receives potassium from the channel and then transfers it to the pump, from where it is transported to the cell. 

A balanced potassium household is critical for the survival of both people and bacteria. As bacteria are exposed to much greater fluctuations in environmental conditions, the controlled intake of potassium often poses a particular challenge. Since the cell membrane is impenetrable for potassium ions, it has to be translocated through specific membrane transport proteins. 

On the one hand, potassium channels enable the rapid, but passive influx of potassium ions. This stops as soon as an electrochemical equilibrium between the cell and its environment has been reached. To attain intracellular concentrations beyond this, potassium is transported into the cell actively through potassium pumps, with energy being consumed in the form of ATP.

Since both protein families – channels and pumps – carry out very different functions, they have always been described as separate from each other. This, however, is contradicted by the observation that KdpFABC, a highly affine, active potassium uptake system of bacteria, does not represent a simple pump, but is constructed of a total of four different proteins. One of these is derived from a typical pump, while another one resembles a potassium channel.

Inga Hänelt, Assistant Professor for biochemistry at Goethe University, and her colleague Cristina Paulino from University of Groningen, the Netherlands, therefore decided to take a closer look at the membrane protein KdpFABC through the microscope – or, more specifically, the cryo-electron microscope. They were surprised by the result: “All earlier hypotheses were wrong,” states Inga Hänelt. “Although we had all the data in front of us, it took us a while to understand the pathway potassium takes through the complex into the cell.”

First, a channel-like protein binds the potassium and transports it through the first tunnel to the pump. Once it has arrived, the first, outward-facing tunnel closes, while a second, inward-facing tunnel opens. This tunnel also extends between both proteins and ultimately ends in the interior of the cell. “The complex essentially combines the best qualities of both protein families,” explains Charlott Stock, doctoral candidate in Inge Hänelt’s research group. “The channel-like protein binds potassium, at first very specifically and with high affinity, while the pump enables an active transport that can enrich potassium in the cell by 10,000-fold.”

The data, recently published in Nature Communications, impressed the scientists with how diverse transport through membranes can be. “We have learned that when investigating various membrane transport proteins, we shouldn’t rely on seemingly incontrovertible mechanisms, but have to be ready for surprises,” summarises Inga Hänelt.

Publication:Charlott Stock, Lisa Hielkema, Igor Tascon, Dorith Wunnicke, Gert T. Oostergetel,  Mikel Azkargorta, Cristina Paulino, Inga Hänelt, Cryo-EM structures of KdpFABC suggest a K+ transport mechanism via two inter-subunit half-channels, in: Nature Communications, 10.1038/s41467-018-07319-2 

An image may be downloaded at: www.uni-frankfurt.de/75137139
Caption: Outward and inward opening structures of KdpFABC in the cell membrane. Credit: Inga Hänelt research group.

Further information: Dr. Inga Hänelt, Institute for Biochemistry, Faculty 14, Riedberg Campus, Telephone: +49 69 798-29262, haenelt@biochem.uni-frankfurt.de 

 

Nov 21 2018
09:18

Friedrich Merz Visiting Professor Donald Ingber cultivates miniature organs on microchips

What are the alternatives to animal testing?

FRANKFURT. How predictive are animal models for the human body? Which human organs can be recreated in vitro? How can personalized medicine benefit from patient-specific organ systems in the future? These questions are the focus of this year’s Friedrich Merz Visiting Fellowship Endowment with Donald Ingber, who will visit Goethe University from Harvard University for one week at the beginning of December. Ingber develops miniature, living organ systems of human cells for investigating diseases and testing new therapies. 

The bioengineering expert developed methods for engineering living human cells on microchips as miniature, three-dimensional organs. These models often deliver more precise results than animal tests, whose predictability for the human body is limited. In addition, they represent a trendsetting option for testing novel drug substances in the laboratory. In cancer therapy, patient-specific tumor cells are cultivated in vitro in order to find a personalized and effective treatment of the individual cancerous disease. 

Professor Ingber and Professor Maike Windbergs, who investigates alternatives to animal testing at Goethe University, will present these fascinating new approaches in a clear and understandable way using film material and examples from research and clinical practice in a podium discussion for the general public

Podium discussion: Human organs and diseases in vitro – fiction or realistic alternative to animal testing?
When: 6th December (Thursday) at 6:00 pm
Where: the Arkadensaal at Goethe House, Großer Hirschgraben 23-25, 60311 Frankfurt. 

Additional podium guests include State Animal Welfare Officer for Hessen Dr. Madeleine Martin and Merz Chief Scientific Officer Dr. Stefan Albrecht. Merz is among the pioneers in the development of in vitro tests for Botolinum toxin.

In a symposium on Wednesday 5th December, international experts will discuss “Modelling health and diseases; form in vitro design to future therapies” (Location: Biozentrum, Riedberg Campus, Hörsaal B1, 9 am – 5 pm). The experts include Professor Andries von der Meer from the Twente University in Enschede, Netherlands. He designs artificial blood vessels on chips and uses them to replicate the process of thrombosis. Professor Ernst Reichmann from the Children’s Clinic in Zurich will present clinical studies on the development of artificial skins for burn victims. The presentation by Professor Stefan Hippenstiel from the Charité in Berlin will discuss the use of human lung tissue to simulate infections in the lung.

Goethe University will be represented by the following experts: Professor Florian Greten, Speaker of the Frankfurt Cancer Institute, who will talk about the use of test systems with human cancer cells for preclinical substance tests and in personalized medicine. Dr. Manuel Kaulich from the Institute for Biochemistry II will report on how he uses the gene scissors CRISPR/Cas for the large-scale screening of substances in order to counter resistances in cancer treatment. Professor Ernst Stelzer from the Buchmann Institute for Molecular Life Sciences at Goethe University and his research group investigates spheroids based on pancreatic cells to test new therapies for type I diabetes. For the first time, three young postdoctoral students in pharmacy and medicine will introduce their work in brief presentations.

Donald Ingber will also give a lecture for students on 6th December at 10:00 am on the same topics (location: Otter-Stern-Centre, Riedberg Campus, HS 3). It will be followed by a one-hour discussion with questions prepared by pharmacy students in their 8th semester.

Professor Donald Ingber is founding director of the Wyss Institute for Biologically Inspired Engineering at Harvard University. Tissue engineering is just one of his many areas of research, which also encompass mechanobiology, tumor angiogenesis, systems biology and nanobiotechnology and translational medicine. He has received numerous awards for his creative ideas. In 2015, the journal “Foreign Policy” elected him as “Leading Global Thinker” and his “Organ-on-the-Chip” technology was awarded “Design of the Year” by the London Design Museum. Ingber holds 150 patents and has founded five companies.

Members of the press will have the opportunity to interview Donald Ingber and other experts on the day of the symposium (5th December). Please contact Professor Maike Windbergs for scheduling: +49 (0) 69 798-42715, windbergs@em.uni-frankfurt.de .

Further information: Professor Maike Windbergs, Institut für Pharmazeutische Technologie, Faculty 14, Riedberg Campus, Tel.: +49 (0) 69 798-42715, windbergs@em.uni-frankfurt.de.
http://www.uni-frankfurt.de/Friedrich-Merz-Stiftungsgastprofessur