Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Switch makes Salmonella stick or twist

06.02.2002


FimZ is the difference between Salmonella sticking(top) or swimming (bottom)
© S. Clegg


Drug leads in protein that sends gut bacteria packing

A protein enables harmful Salmonella bacteria to switch from clinging to our gut lining to swimming off. This get-up-and-go is so crucial to Salmonella’s survival that the protein could prove to be a good target for drugs.

The Salmonella variant Typhimurium causes around 1.4 million cases of food poisoning in the United States each year, and about 1,000 deaths - mainly among infants and the elderly. The bug grips the gut wall to cause infection, and swims off to avoid immune-system attacks or to infect another host.



Steven Clegg at the University of Iowa in Iowa City and Kelly Hughes at the University of Washington in Seattle find that letting go is hard to do if the bacterium produces too much of a protein called FimZ.

This protein makes the bacterium grow sticky filaments, called fimbriae, which lash it to the gut lining. When FimZ production is switched off, the bacteria instead make smooth hairs called flagella. Spinning like propellers, these move the bugs around.

Mutant bacteria that produce too much FimZ cannot budge, even in conditions that normally send them packing, Clegg and Hughes report. Conversely, forcing the bugs to make too little of the protein could stop them sticking to surfaces, the researchers hope.

"It’s a very promising angle of attack," says Ian Blomfield, who studies gut bacteria at the University of Kent in Canterbury, UK. He has identified a similar molecular switch in highly infectious Escherichia coli bacteria, which he is patenting as a potential drug target.

Inside out

Clegg and Hughes suspect that FimZ is half of a two-component system. Many bacteria use such protein pairs to sense their surroundings.

Disrupting FimZ production inside Salmonella may be enough to stop the microbes in their tracks. But blocking the other protein, which sits on the outside of the bacteria, might work even better. This would blind a bug to the subtle chemical cues that tell it whether to stay or go.

"If you can knock out that molecule, the bacteria won’t be able to interact with their environment," says Clegg. He hopes that more cellular sleuthing will identify the external molecule, which is a tempting target for future drugs or vaccines.

References

  1. Clegg, S. & Hughes, K. T. FimZ is a molecular link between sticking and swimming in Salmonella enterica serovar Typhimurium. Journal of Bacteriology, 184, 1209 - 1213, (2002).


TOM CLARKE | © Nature News Service

More articles from Health and Medicine:

nachricht New combination therapy established as safe and effective for prostate cancer
26.06.2019 | Society of Nuclear Medicine and Molecular Imaging

nachricht Novel model for studying intestinal parasite could advance vaccine development
26.06.2019 | University of Pennsylvania

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Fraunhofer IDMT demonstrates its method for acoustic quality inspection at »Sensor+Test 2019« in Nürnberg

From June 25th to 27th 2019, the Fraunhofer Institute for Digital Media Technology IDMT in Ilmenau (Germany) will be presenting a new solution for acoustic quality inspection allowing contact-free, non-destructive testing of manufactured parts and components. The method which has reached Technology Readiness Level 6 already, is currently being successfully tested in practical use together with a number of industrial partners.

Reducing machine downtime, manufacturing defects, and excessive scrap

Im Focus: Successfully Tested in Praxis: Bidirectional Sensor Technology Optimizes Laser Material Deposition

The quality of additively manufactured components depends not only on the manufacturing process, but also on the inline process control. The process control ensures a reliable coating process because it detects deviations from the target geometry immediately. At LASER World of PHOTONICS 2019, the Fraunhofer Institute for Laser Technology ILT will be demonstrating how well bi-directional sensor technology can already be used for Laser Material Deposition (LMD) in combination with commercial optics at booth A2.431.

Fraunhofer ILT has been developing optical sensor technology specifically for production measurement technology for around 10 years. In particular, its »bd-1«...

Im Focus: The hidden structure of the periodic system

The well-known representation of chemical elements is just one example of how objects can be arranged and classified

The periodic table of elements that most chemistry books depict is only one special case. This tabular overview of the chemical elements, which goes back to...

Im Focus: MPSD team discovers light-induced ferroelectricity in strontium titanate

Light can be used not only to measure materials’ properties, but also to change them. Especially interesting are those cases in which the function of a material can be modified, such as its ability to conduct electricity or to store information in its magnetic state. A team led by Andrea Cavalleri from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg used terahertz frequency light pulses to transform a non-ferroelectric material into a ferroelectric one.

Ferroelectricity is a state in which the constituent lattice “looks” in one specific direction, forming a macroscopic electrical polarisation. The ability to...

Im Focus: Determining the Earth’s gravity field more accurately than ever before

Researchers at TU Graz calculate the most accurate gravity field determination of the Earth using 1.16 billion satellite measurements. This yields valuable knowledge for climate research.

The Earth’s gravity fluctuates from place to place. Geodesists use this phenomenon to observe geodynamic and climatological processes. Using...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on UV LED Technologies & Applications – ICULTA 2020 | Call for Abstracts

24.06.2019 | Event News

SEMANTiCS 2019 brings together industry leaders and data scientists in Karlsruhe

29.04.2019 | Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

 
Latest News

Shell increases versatility of nanowires

26.06.2019 | Materials Sciences

Hubble finds tiny 'electric soccer balls' in space, helps solve interstellar mystery

26.06.2019 | Physics and Astronomy

New combination therapy established as safe and effective for prostate cancer

26.06.2019 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>