Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Molecular technique shows promise in destroying drug resistance in bacteria

15.11.2004


A new approach to outwit resistance to antibiotics has been discovered by a team of researchers at the University of Illinois at Urbana-Champaign.



By inserting a naturally occurring molecule into an antibiotic-resistant bacterium, the team was able to gradually destroy the machinery responsible for the resistance. "Multidrug-resistant bacteria are now ubiquitous in both hospital settings and the larger community," wrote Paul J. Hergenrother, a professor of chemistry, in a paper that appeared online ahead of publication in the Journal of the American Chemical Society. "Clearly, new strategies and targets are needed to combat drug-resistant bacteria."

Antibiotic resistance makes it difficult to fight infection and increases the chance of acquiring one while in a hospital. That, in turn, has led to more deaths from infection, longer hospital stays and a greater use of more toxic and expensive drugs, according to the National Institutes of Health.


Resistance occurs when bacteria develop ways to make themselves impervious, such as by pumping antibiotics out of the cell, preventing them from entering the cell or demolishing them. A common way bacteria develop resistance is by laterally transferring plasmids -- pieces of extra-chromosomal DNA -- from one bacterium to another. These plasmids contain genetic codes for proteins that make bacteria insensitive to antibiotics. "Our idea was that if you could eliminate plasmids that make the bacterium resistant, then the bacterium could be sensitive to antibiotics again," Hergenrother said. The researchers’ approach was to use a natural process called plasmid incompatibility. "If there is one plasmid in a cell and another one is introduced, then they compete with each other for resources," Hergenrother said. "One of them wins and the other is eliminated."

With the help of chemistry graduate students Johna C.B. DeNap, Jason R. Thomas and Dinty J. Musk, Hergenrother developed a technique that mimicked plasmid incompatibility by incubating bacteria containing plasmids with a specific compound -- in this case an aminoglycoside called apramycin that binds to plasmid-encoded RNA and prevents proper plasmid reproduction.

Apramycin was chosen after numerous potential aminoglycosides -- a group of antibiotics effective against gram-negative bacteria -- were tested to find those that bind tightly to the target plasmids. Positively charged apramycin bound to negatively charged plasmid-encoded RNA, which allowed apramycin to prevent the actions of the protein that triggers plasmid reproduction. By thwarting that protein, apramycin blocked plasmid replication.

The apramycin treatment was applied to bacterial cultures that were grown for 250 generations. By the end of the experiment, the plasmids no longer were present, making it possible for antibiotics to work. "This is the first demonstration of a mechanistic-based approach to systematically eliminate the plasmids," Hergenrother said. "Standard antibiotics target the cell wall, but as resistance to antibiotics emerges, there needs to be other targets. We validated that plasmids as a new target for antibiotics."

Further studies are needed to identify whether apramycin is useful against the plasmids occurring in different strains of antibiotic-resistant bacteria. It is possible that other compounds may be needed to target specific plasmids, Hergenrother said. Future studies in his lab will investigate those questions.

Jim Barlow | EurekAlert!
Further information:
http://www.uiuc.edu

More articles from Life Sciences:

nachricht Ambush in a petri dish
24.11.2017 | Friedrich-Schiller-Universität Jena

nachricht Meadows beat out shrubs when it comes to storing carbon
23.11.2017 | Norwegian University of Science and Technology

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: New proton record: Researchers measure magnetic moment with greatest possible precision

High-precision measurement of the g-factor eleven times more precise than before / Results indicate a strong similarity between protons and antiprotons

The magnetic moment of an individual proton is inconceivably small, but can still be quantified. The basis for undertaking this measurement was laid over ten...

Im Focus: Frictional Heat Powers Hydrothermal Activity on Enceladus

Computer simulation shows how the icy moon heats water in a porous rock core

Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

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...

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

IceCube experiment finds Earth can block high-energy particles from nuclear reactions

24.11.2017 | Physics and Astronomy

A 'half-hearted' solution to one-sided heart failure

24.11.2017 | Health and Medicine

Heidelberg Researchers Study Unique Underwater Stalactites

24.11.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>