Friday , July 30 2021

Tübingen researchers reveal a stealthy strategy of multiresistant germs

Keep in mind the due period until Wednesday, November 21, 2018, at 7:00 PM CET / 6:00 PM London time

Researchers at the University of Tübingen and the German Infection Research Center (DZIF) have achieved an advance in the decryption of germs of multilevel disease. The team led by Professor Andreas Peschel and Professor Thilo Stehle was able to clarify the structure and function of a previously unknown protein, with the help of which it was feared that pathogens like Staphylococcus aureus protect against the human immune system as with an invisible mantle. The study was published Wednesday in Nature magazine.

Bacterial infections such as Staphylococcus aureus cause many deaths worldwide. Especially feared in hospitals are strains resistant to antibiotic methicillin, strains of Staphylococcus aureus or MRSA for short. According to a study published in early November, there were about 670,000 multi-resistant pathogens in the EU only in the year 2015. 33,000 patients died.

As a general rule, our immune system faces well with pathogens such as bacteria or viruses. In some germs, however, the human body's defensive strategies fail, especially in immunocompromised patients. Unfortunately, antibiotics are not effective against resistant pathogens. Effective replacement antibiotics and a protective vaccine against MRSA are still not visible. A precise understanding of defense mechanisms could allow new therapies against bacteria.

Researchers from the University of Tübingen have described how MRSA germs are invisible to the immune system. They demonstrated that many of the particularly common MRSA germs have acquired a previously unknown protein, which means that pathogens are no longer recognized by immune system antibodies. Tübingen scientists gave the protein the name TarP (short for the texricotic acid Rbitol P).

"TarP is changing the pattern of sugar molecules on the pathogenic surface in a never-before-seen way," said Professor Andreas Peschel of the Interfaculty Institute for Microbiology and Medicine of Infection at the University of Tübingen. "This means that the immune system can not produce antibodies to the most important MRSA antigen," Diacapid Acid. " The immune system is not only "blind". It also loses the most important weapon against the pathogen.

Reprogrammed by fags
Tübingen researchers assume that the bacterial mantle of invisibility is the result of a conflict between pathogens and their natural enemies, the so-called fags. A bacteriophage is a kind of virus that attacks bacteria, uses them as a host cell and feeds them. In this case, the phage apparently has reprogrammed its host using the TarP protein, thus modifying the surface of the bacterium.

The first authors of the work, David Gerlach and Yinglan Guo, were able to clarify the mechanism and the structure of TarP. "We now understand in detail how the protein works at the molecular level as an enzyme," Gerlach said. TarP structure-function analysis is an excellent base for the development of new active substances that block the TARP and that the pathogen is recognizable for the immune system. Particularly important for the success of this work was an interdisciplinary approach, involving other scientists from Denmark, Germany, Great Britain, Italy, the Netherlands and South Korea.

"The discovery of TarP was a complete surprise. It explains very well why the immune system often has no chances against MRSA," said Professor Thilo Stehle of the Interfaculty Institute for Biochemistry. "The results available now will help us develop better therapies and vaccines against pathogens." Peschel referred to the recently approved Tübingen Excellence Cluster "Controlling microbes to fight infections" and the close participation in the German Center for the Research of Infection: "This is excellent Network will help us keep moving forward in the MRSA and TarP scanning ".

High resolution image at
Note the source!

scientific contact:
Prof. Dr. Andreas Peschel
University of Tübingen
Instituto Interfaculty de Microbiología y Medicina de la Infección
Telephone +49 7071 29-78855
[email protected]

Prof. Dr. Thilo Stehle
University of Tübingen
Institut Interfaculty de Bioquímica
Telephone +49 7071 29-73043
[email protected]

Original post:
Gerlach, Guo et al., 2018, Glucosilation of the cell wall of Staphylococcus aureus resistant to methicillin to evade immunity. Nature, DOI: 10.1038 / s41586-018-0730-x (available only after the expiration of the seizure: Wednesday, November 21, 2018, 7:00 p.m. CET)

id 2018/11

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