The bacteria whisperer

DESY's new Lead Scientist Holger Sondermann eavesdrops on bacterial colonies

Holger Sondermann (DESY)

New DESY Lead Scientist at CSSB: Holger Sondermann. (Image: DESY)

Bacteria Pseudomonas aeruginosa

Sondermann's object of study, the bacteria Pseudomonas aeruginosa, under the electron microscope.

The latest addition to DESY's team of Lead Scientists is the first biologist among many physicists. Holger Sondermann has been working at the Center for Structural Systems Biology (CSSB) and as a professor at the Kiel University (CAU) since the beginning of August to lead a team of scientists that will observe the communication between bacteria – and might find new approaches to combat pathogens along the way.

Bacteria feel at home where it’s warm and humid. They form colonies that establish themselves as a persistent mucus in the bacteria's feel-good zone. This mucus is called biofilm, and biologist and biochemist Holger Sondermann investigates how it develops – and how it might be eliminated. "The biofilm is a kind of social network in which different cells take on different tasks," the researcher explains. "It has been shown that biofilms are the preferred form of existence for many bacteria. Correspondingly, the fact that the bacteria flock together is anything but a coincidence: these supposedly simple unicellular organisms can control colony formation themselves, depending on their environmental conditions. To do this, they flip a switch that triggers the production of a specific messenger substance. This ensures that many bacteria - even different species - join together to form a biofilm. However, if external conditions change, for example the availability of food, the process can be reversed and they all go their own ways again.

Sondermann wants to better understand how bacteria form biofilms with the help of X-ray crystallography and complementary techniques. He wants to know how the signal is transmitted and what happens afterwards. Although his research is directed towards a fundamental understanding of the process there is a wide range of possible applications. For example, biofilms often appear in connection with chronic diseases – when bacterial colonies form in catheters and cause infections, in cystic fibrosis sufferers or even in burns, to name just a few. "If we understand the communication process between the bacteria precisely, we might be able to manipulate it," he says. "That way, we could dissolve it or prevent it from forming in the first place.” Perhaps it would also be possible to develop materials on which no biofilm can form. On the other hand, the formation of useful biofilms could be influenced, for example in the intestine or in the soil.

Born in Cologne, Sondermann came to DESY Photon Science through a joint appointment with the CAU in Kiel. He is enthusiastic about his new environment: the research infrastructure at DESY and at CSSB, the proximity to the accelerator, the European Molecular Biology Laboratory EMBL and the various experimental platforms offer him many opportunities to further develop his field of expertise. He also likes the proximity to physics and other disciplines on campus. "Physics offers new strategies that we have not yet applied to our problems in this way," he says. For example, he is considering incorporating artificial intelligence into his research. "For the complex genome and image analyses, the human eye or a clever spreadsheets are simply not good enough.”

After completing his doctorate at the Max Planck Institute for Biochemistry in Martinsried, during which he also discovered structural biology, Sondermann first went to Rockefeller University in New York and did research in Berkeley, California. He then spent many years at Cornell University in New York State (US) before moving with his family to Hamburg this year.

Holger Sondermann's research page (at CSSB)