Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Putting bacterial antibiotic resistance into reverse

26.04.2010
The use of antibiotics to treat bacterial infections causes a continual and vicious cycle in which antibiotic treatment leads to the emergence and spread of resistant strains, forcing the use of additional drugs leading to further multi-drug resistance.

But what if it doesn't have to be that way?

In a presentation at the American Society for Biochemistry and Molecular Biology's annual meeting, titled "Driving backwards the evolution of antibiotic resistance," Harvard researcher Roy Kishony will discuss his recent work showing that some drug combinations can stop or even reverse the normal trend, favoring bacteria that do not develop resistance. The talk will be in Anaheim Convention Center Room 304D, on Sunday April 25 at 3:30 pm PST.

"Normally, when clinicians administer a multi-drug regimen, they do so because the drugs act synergistically and speed up bacterial killing," Kishony explains. However, Kishony's laboratory has focused on the opposite phenomenon: antibiotic interactions that have a suppressive effect, namely when the combined inhibitory effect of using the two drugs together is weaker than that of one of the drugs alone.

Kishony and his team identified the suppressive interaction in E. coli, discovering that a combination of tetracycline – which prevents bacteria from making proteins – and ciprofloxacin – which prevents them from copying their DNA – was not as good as slowing down bacterial growth as one of the antibiotics (ciprofloxacin) by itself.

Kishony notes that this suppressive interaction can halt bacterial evolution, because any bacteria that develop a resistance to tetracycline will lose its suppressive effect against ciprofloxacin and die off; therefore, in a population the bacteria that remain non-resistant become the dominant strain.

While such a weakened antibiotic combination is not great from a clinical standpoint, the Kishony lab is using this discovery to set up a drug screening system that could identify novel drug combinations that could hinder the development of resistance but still act highly effectively. "Typical drug searches look for absolute killing effects, and choose the strongest candidates," he says. "Our approach is going to ask how these drugs affect the competition between resistant versus sensitive bacterial strains."

To develop such a screen, Kishony and his group first had to figure how this unusual interaction works.

"Fast growing bacteria like E. coli are optimized to balance their protein and DNA activity to grow and divide as quickly as the surrounding environment allows," Kishony explains. "However, when we exposed E. coli to the ciprofloxacin, we found that their optimization disappeared."

"We expected that since the bacteria would have more difficulty copying DNA, they would slow down their protein synthesis, too," Kishony continues. "But they didn't; they kept churning out proteins, which only added to their stress." However, once they added the tetracycline and protein synthesis was also reduced in the E. coli, they actually grew better than before. They then confirmed the idea that production of ribosomes - the cell components that make proteins - is too high under DNA stress by engineering E. coli strains that have fewer ribosomes than regular bacteria. While these mutants grew a more slowly in normal conditions, they grew faster under ciprofloxacin inhibition of DNA synthesis.

Kishony notes that their preliminary work on the development of a screen for drugs that put resistance in a disadvantage looks promising, and hopes that it would lead to the identification of novel drugs that select against resistance.

NOTE TO EDITORS: The American Society for Biochemistry and Molecular Biology annual meeting is part of the Experimental Biology 2010 conference that will be held April 24-28, 2010 at the Anaheim Convention Center. The press is invited to attend or to make an appointment to interview Dr. Kishony. Please contact Nicole Kresge at 202.316.5447 or nkresge@asbmb.org.

The American Society for Biochemistry and Molecular Biology (www.asbmb.org) is a nonprofit scientific and educational organization with over 12,000 members. Founded in 1906, the Society is based in Bethesda, Maryland, on the campus of the Federation of American Societies for Experimental Biology. The Society's purpose is to advance the science of biochemistry and molecular biology through publication of scientific and educational journals: the Journal of Biological Chemistry, Molecular & Cellular Proteomics, and the Journal of Lipid Research, organization of scientific meetings, advocacy for funding of basic research and education, support of science education at all levels, and promoting the diversity of individuals entering the scientific workforce.

Nicole Kresge | EurekAlert!
Further information:
http://www.asbmb.org

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Supersensitive through quantum entanglement

28.06.2017 | Physics and Astronomy

X-ray photoelectron spectroscopy under real ambient pressure conditions

28.06.2017 | Physics and Astronomy

Mice provide insight into genetics of autism spectrum disorders

28.06.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>