Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Researchers describe structures, mechanisms that enable bacteria to resist antibiotics


Two new discoveries from Edward Yu's Iowa State University laboratory are adding to the scientific understanding of how bacteria resist antibiotics.

Yu and his research group have just described two structures and mechanisms - efflux pumps and reinforced cell walls - that certain disease-causing bacteria use to keep antibiotics away. That understanding could one day lead to new treatments that disable the structures and restore the effectiveness of drugs.

This is a ribbon diagram of the three-part efflux pump of the Campylobacter jejuni bacterium.

Credit: Edward Yu/Iowa State University

"We study a lot of efflux pumps to understand antibiotic resistance," said Yu, an Iowa State professor with appointments in physics and astronomy; chemistry; biochemistry, biophysics and molecular biology; and the U.S. Department of Energy's Ames Laboratory. "Cell wall remodeling is also a major mechanism to work against antibacterial drugs.

"The structure and mechanism depend on the bacteria you're talking about - and the bacteria will find a way."

Two journals have just published the latest findings by Yu's research group:

  1. A paper published online by Nature Communications describes how the Campylobacter jejuni bacterium, which causes a digestive tract inflammation (enterocolitis) and associated diarrhea, uses a three-molecule efflux pump to extrude antibacterial drugs. The project is a collaboration of Yu; Yeon-Kyun Shin, Iowa State's Roy J. Carver Professor of Biochemistry, Biophysics and Molecular Biology; and Qijing Zhang, an Iowa State associate dean of veterinary medicine and the Dr. Frank K. Ramsey Endowed Chair in Veterinary Research. Chih-Chia "Jack" Su, an Iowa State associate scientist; Linxiang Yin, an Iowa State graduate student; and Nitin Kumar, an Iowa State doctoral student; are first authors.


    Previous studies reported the three molecules of the pump worked in a synchronized rotation - one molecule accessing, one molecule binding and one molecule extruding - to pump antibiotics from the cell. Yu's research group found that each part of the pump worked independently of the others, essentially creating three pumps in one structure.

    "The three independent pumps make it a more powerful multidrug efflux pump," Yu said.


  2. A paper published online by the Proceedings of the National Academy of Sciences Early Edition describes how the Burkholderia multivorans bacterium, which can cause pneumonia in people with immune deficiencies or lung diseases such as cystic fibrosis, is able to remodel and strengthen its cell wall, closing the door to a range of antimicrobial drugs. Kumar and Su are first authors.


    The paper focuses on how these bacteria transport hopanoid lipid compounds to their outer cell membranes. The compounds contribute to membrane stability and stiffness.

"Overall our data suggest a novel mechanism for hopanoid transport involved in cell wall remodeling, which is critical for mediating multidrug resistance in Burkholderia," the authors wrote in a project summary.

Grants from the National Institutes of Health supported both studies. Grants from the U.S. Department of Energy also supported ultra-bright, high-energy X-ray experiments at the Advanced Photon Source at Argonne National Laboratory in Illinois.

Yu and his research group have a long history of successfully using X-ray crystallography to describe and understand the structure of pumps, transporters and regulators in bacteria. A gallery on his research group's website shows ribbon diagrams of 21 different structures.

Because of Yu's significant contribution to the understanding of antimicrobial resistance in bacteria, the American Academy of Microbiology elected him to be an academy fellow earlier this year.

With that comprehensive understanding of the structures and mechanisms behind bacterial resistance to antibiotics, Yu said his research group is beginning to look at how the pumps and transporters can be turned off.

"We're trying to find an inhibitor compound," Yu said. "We're thinking about doing a little more translational science. We have a lot of rich information about the structure and function of these pumps. Why not use it?"

Media Contact

Edward Yu


Edward Yu | EurekAlert!

Further reports about: antibacterial drugs antibiotics bacteria bacterium drugs pump

More articles from Life Sciences:

nachricht Don't Give the Slightest Chance to Toxic Elements in Medicinal Products
23.03.2018 | Physikalisch-Technische Bundesanstalt (PTB)

nachricht North and South Cooperation to Combat Tuberculosis
22.03.2018 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Space observation with radar to secure Germany's space infrastructure

Satellites in near-Earth orbit are at risk due to the steady increase in space debris. But their mission in the areas of telecommunications, navigation or weather forecasts is essential for society. Fraunhofer FHR therefore develops radar-based systems which allow the detection, tracking and cataloging of even the smallest particles of debris. Satellite operators who have access to our data are in a better position to plan evasive maneuvers and prevent destructive collisions. From April, 25-29 2018, Fraunhofer FHR and its partners will exhibit the complementary radar systems TIRA and GESTRA as well as the latest radar techniques for space observation across three stands at the ILA Berlin.

The "traffic situation" in space is very tense: the Earth is currently being orbited not only by countless satellites but also by a large volume of space...

Im Focus: Researchers Discover New Anti-Cancer Protein

An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.

The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...

Im Focus: Researchers at Fraunhofer monitor re-entry of Chinese space station Tiangong-1

In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.

Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...

Im Focus: Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.

They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...

Im Focus: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

New solar solutions for sustainable buildings and cities

23.03.2018 | Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

Latest News

For graphite pellets, just add elbow grease

23.03.2018 | Materials Sciences

Unique communication strategy discovered in stem cell pathway controlling plant growth

23.03.2018 | Agricultural and Forestry Science

Sharpening the X-ray view of the nanocosm

23.03.2018 | Physics and Astronomy

Science & Research
Overview of more VideoLinks >>>