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 Routing gene therapy directly into the brain
07.12.2017 | Boston Children's Hospital

nachricht New Hope for Cancer Therapies: Targeted Monitoring may help Improve Tumor Treatment
01.12.2017 | Berliner Institut für Gesundheitsforschung / Berlin Institute of Health (BIH)

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: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Long-lived storage of a photonic qubit for worldwide teleportation

12.12.2017 | Physics and Astronomy

Multi-year submarine-canyon study challenges textbook theories about turbidity currents

12.12.2017 | Earth Sciences

Electromagnetic water cloak eliminates drag and wake

12.12.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>