Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New findings in the war on the tubercle bacterium

09.03.2011
Tuberculosis kills two million people each year and is once again gaining ground also in Sweden and other Western countries. Researchers at Linköping University in Sweden are now presenting new findings that show how the tubercle bacterium manages to survive inside the body’s macrophage cells in order eventually to blow them up and spread their infection.

The bacterium Mycobacterium tuberculosis is a successful organism that lives in an estimated one third of the world’s population. But only about five percent of those infected develop the disease.

“We also know that many people do not become infected despite exposure to the infection. This is a question we are looking for an answer to,” says Amanda Welin, who is now presenting her doctoral dissertation in medical microbiology.

The research group has studied phenomena in both the bacterium and the macrophage, whose task is to knock out infectious substances that get into the body.

One weapon is enzymes, which make the ingested bacteria feel sickly. Enzymes work best in acidic environments, with a pH level under 6. For their part, the bacteria can strike back by releasing substances that prevent the pH level from going down. Amanda Welin has shown that this warfare is directly reflected in the growth or reduction of bacteria.

These bacteria also have a capacity to kill macrophages and spread to new cells. Welin shows that this is done by having a tiny protein cause cell death, necrosis, which in turn leads to inflammation of the tissue.

To carry out these studies, Amanda Welin and her colleagues developed a new method for determining the number of bacteria inside a cell. They use a gene from sea-fire organisms, which cause strange lights in seawater at night. When this gene is added to the genes of the bacterium, the bacterium begins to produce the same luminescent substance, luciferase, as the sea-fire organism does. Thanks to this, it’s possible to monitor developments inside the macrophage – the intensity of the light radiating outward corresponds to the number of bacteria inside. If their number grows, this indicates that they have begun to multiply inside the human cell.

The method can be used to search for plausible drug candidates. In that field, the Linköping scientists are collaborating with a group of colleagues in Sudan, who are testing, among other things, various medicinal plants with substances that could possibly be used as active ingredients to combat tuberculosis.

The dissertation Survival strategies of Mycobacterium tuberculosis inside the human macrophage is published by LiU Electronic Press, It was publicly defended at Linköping University on March 4, 2011.

Contact:Amanda Welin: mobile phone: +46 (0)705-464749, amanda.welin@liu.se

Anika Agebjörn | idw
Further information:
http://www.vr.se
http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-65452

More articles from Life Sciences:

nachricht Could this protein protect people against coronary artery disease?
17.11.2017 | University of North Carolina Health Care

nachricht Microbial resident enables beetles to feed on a leafy diet
17.11.2017 | Max-Planck-Institut für chemische Ökologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>