Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UNC scientists unveil a superbug’s secret to antibiotic resistance

31.01.2013
Worldwide, many strains of the bacterium Staphyloccocus aureus are already resistant to all antibiotics except vancomycin. But as bacteria are becoming resistant to this once powerful antidote, S. aureus has moved one step closer to becoming an unstoppable killer.

Now, researchers at the University of North Carolina at Chapel Hill have not only identified the mechanism by which vancomycin resistance spreads from one bacterium to the next, but also have suggested ways to potentially stop the transfer.

The work, led by Matthew Redinbo, professor of chemistry at UNC’s College of Arts and Sciences, addresses the looming threat of incurable staph infections – a global public health problem that has mobilized scientists across disciplines to work together to identify the Achilles heel of these antibiotic-resistant bacteria.

“We used to live in a world where antibiotics could readily cure bacterial disease,” said Redinbo. “But this is clearly no longer the case. We need to understand how bacteria obtain resistance to drugs like vancomycin, which served for decades as the ‘antibiotic of last resort.’”

In his work, Redinbo and his team targeted a bacterial enzyme known as Nicking Enzyme in Staphyloccoccus, or NES. The enzyme has long been known to interact with plasmids, circular pieces of double-stranded DNA within bacteria that are physically separate from the bacterial chromosome. Plasmids commonly contain antibiotic-resistance genes, and can make the machinery necessary to transfer these genes from an infected bacterium to an uninfected one.

By revealing the crystal structure of NES, the researchers found that this enzyme nicks one strand of the plasmid at a very specific site—and in a very specific way. It turns out that NES forms two loops that work together to pinch one strand of the plasmid at a particular groove in the DNA to cut it. This strand is now free to leave its host and transfer to a nearby bacterium, making them resistant to vancomycin.

Moreover, Redinbo was able to capture a snapshot of the enzyme bound to the plasmid. “As a structural biologist, it’s all about the pictures for me,” said Redinbo. “And it was this picture that confirmed the precise location on which NES works.”

With this information, Redinbo knew the groove on the DNA that the enzyme recognize and could design a small synthetic molecule that would sit on this groove and block NES. Teaming up with colleagues at the California Institute of Technology, Redinbo did just that. The molecule prevented NES from nicking the DNA, which could prevent the resistance genes from spreading.

According to Redinbo and colleagues, this small synthetic molecule could help guide future research aimed at developing effective therapies for strains of antibiotic-resistant S. aureus.

“This is really exciting for us,” said Redinbo, who is also a professor at UNC’s School of Medicine and a member of the Lineberger Comprehensive Cancer Center. “It opens the door for potentially stopping the spread of antibiotic resistance—and that’s exactly what we need in this post-antibiotic era.”

The work was published this week in the online early edition of the Proceedings of the National Academy of Sciences.

Media note: Matthew Redinbo can be contacted at (919) 962-4504, redinbo@unc.edu

College of Arts and Sciences contact: Dee Reid, (919) 843-6339, deereid@unc.edu

News Services contact: Thania Benios, (919) 962-8596, thania_benios@unc.edu

Thania Benios | EurekAlert!
Further information:
http://www.unc.edu

Further reports about: Arts Arts and Sciences DNA NES UNC resistance genes synthetic molecule

More articles from Life Sciences:

nachricht A Map of the Cell’s Power Station
18.08.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht On the way to developing a new active ingredient against chronic infections
18.08.2017 | Deutsches Zentrum für Infektionsforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>