In a finding that broadens our understanding of how the immune system can detect infection, researchers have identified a previously unappreciated way in which bacteria can be recognized inside our cells.
Many bacteria cause disease by invading cells and creating a safe niche in which to replicate. Cells respond to the infection by activating the immune system, and a chief challenge for bacteria is to avoid immune detection. Prior research had shown that bacteria inside the cytosol (the cells expansive gel-like compartment) could be detected, but how bacteria within the cytosol are recognized has not been clear.
In the new work, Dr. John Brumell and colleagues at The Hospital for Sick Children studied the fate of Salmonella bacteria within the cytosol. These bacteria normally occupy vacuoles in host cells, but under some conditions they leave the vacuole and enter the cytosol. In this foreign environment, the bacteria were recognized by the ubiquitin system, a protein machine that applies molecular tags to cellular proteins to target them for destruction by the proteasome, essentially a molecular shredding device inside mammalian cells. These findings suggest that bacterial proteins are being destroyed by the proteasome within the cytosol during infection, and that this may play a key role in activation of the immune system. A surprising result came when Salmonella was compared with Listeria, a bacterium which normally occupies the cytosol. Listeria avoided recognition by the ubiquitin system by moving within this compartment. This suggests that Listeria and other bacteria that can colonize the cytosol do so in a manner that prevents activation of the immune system.
Heidi Hardman | EurekAlert!
Newly designed molecule binds nitrogen
23.02.2018 | Julius-Maximilians-Universität Würzburg
Atomic Design by Water
23.02.2018 | Max-Planck-Institut für Eisenforschung GmbH
A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.
In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...
A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.
By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
23.02.2018 | Physics and Astronomy
23.02.2018 | Health and Medicine
23.02.2018 | Physics and Astronomy