Oct 122017

Illustration of the MphR biosensor binding to its target DNA sequence. Credit: Edward Kalkreuter

Researchers from North Carolina State University have engineered designer biosensors that can detect antibiotic molecules of interest. The biosensors are a first step toward creating antibiotic-producing “factories” within microbes such as E. coli.

Macrolides are a group of naturally occurring small molecules that can have antibiotic, antifungal or anticancer effects. The antibiotic erythromycin is one example – it is a macrolide produced by soil-dwelling bacteria. Researchers are interested in using these natural antibiotics and the microbes that produce them in order to develop new antibiotics; however, microbes that produce antibiotic macrolides only make small amounts of a limited variety of antibiotics.

“Our ultimate goal is to engineer microbes to make new versions of these antibiotics for our use, which will drastically reduce the amount of time and money necessary for new drug testing and development,” says Gavin Williams, associate professor of bio-organic chemistry at NC State and corresponding author of a paper describing the research. “In order to do that, we first need to be able to detect the antibiotic molecules of interest produced by the microbes.”

Williams and his team used a naturally occurring molecular switch – a protein called MphR – as their biosensor. In E. coli, MphR can detect the presence of macrolide antibiotics being secreted by microbes that are attacking E. coli. When MphR senses the antibiotic, it turns on a resistance mechanism to negate the antibiotic’s effects.

The researchers created a large library of MphR protein variants and screened them for the ability to switch on production of a fluorescent green protein when they were in the presence of a desired macrolide. They tested the variants against erythromycin, which MphR already recognizes, and found that some of the MphR variants improved their detection ability tenfold. They also successfully tested the variants against macrolides that were not closely related to erythromycin, such as tylosin.

“Essentially we have co-opted and evolved the MphR sensor system, increasing its sensitivity in recognizing the molecules that we’re interested in,” says Williams. “We know that we can tailor this biosensor and that it will detect the molecules we’re interested in, which will enable us to screen millions of different strains quickly. This is the first step toward high-throughput engineering of antibiotics, where we create vast libraries of genetically modified strains and variants of microbes in order to find the few strains and variants that produce the desired molecule in the desired yield.”

Learn more: Designer Biosensor Can Detect Antibiotic Production by Microbes


The Latest on: Antibiotics
  • British scientists delay antibiotics timebomb
    on October 21, 2017 at 4:01 pm

    British scientists say they have found a way to delay the day when common infections kill us because antibiotics have lost their effectiveness. Combining antibiotics with metal compounds can boost the drugs’ power, buying time for doctors in the fight ... […]

  • Can Calves Become Resistant to Antibiotics?
    on October 20, 2017 at 5:16 am

    Feeding waste milk is a common practice on many U.S. dairy farms and calf facilities. USDA estimates more than half of all dairies feed whole milk, representing more than 70% of the heifer calves raised in the U.S. “Waste” milk might contain ... […]

  • The Promise and Failure of Antibiotics
    on October 20, 2017 at 2:36 am

    In 2013 the American Academy of Pediatrics began encouraging doctors to treat certain ear infections with what they called “watchful waiting,” an attempt to combat the skyrocketing incidence of antibacterial resistance that was due in part to the ... […]

  • Antibiotics May Reduce Infection Risk Post-Colorectal CA Surgery
    on October 19, 2017 at 10:32 pm

    HealthDay News — For patients undergoing left colon and rectal cancer resections, the addition of oral antibiotics to mechanical bowel preparation (MBP) is associated with a reduced rate of surgical site infections (SSIs), according to a study published ... […]

  • Resistant Bacteria vs. Antibiotics: A Fiercely Fought Battle
    on October 19, 2017 at 7:45 am

    Antibiotics are an integral part of today’s medicine, not only to treat a strep throat or an ear infection – they also play a huge role in routine operations like appendecotomies or cecareans, and they are indispensable as co-treatment for many ... […]

  • Phages an effective alternative to the use of antibiotics in aquaculture
    on October 19, 2017 at 7:24 am

    Researchers from AZTI, Biopolis S.L. (Spain), University of Aveiro (Portugal) and the Aguacircia Aquaculture company (Portugal) have evaluated the impact of the use of bacteriophages that fight the pathogens responsible for diseases that affect species ... […]

  • What You Should Eat During and After Antibiotics
    on October 19, 2017 at 3:16 am

    Antibiotics are a powerful line of defense against bacterial infections. However, they can sometimes cause side effects, such as diarrhea and liver damage. Some foods can reduce these side effects, while others may make them worse. Antibiotics are a type ... […]

  • Should You Stop Taking Antibiotics When Feeling Better?
    on October 19, 2017 at 2:20 am

    According to new research, taking antibiotics when no longer needed may increase antibiotic resistance. The Doctors welcome gastroenterologist Dr. Partha Nandi and infectious disease expert Dr. Brad Spellberg to discuss whether you should stop taking your ... […]

  • When to Say No to Antibiotics for Infection
    on October 16, 2017 at 10:08 am

    Consumer Reports has no financial relationship with advertisers on this site. Every year, doctors prescribe millions of antibiotics. But about a third of the antibiotics prescribed in doctors’ offices are unnecessary, according to a report released ... […]

  • Macrolide Antibiotics Market by Indication, Drugs, Administration, Analysis and Forecasts To 2023
    on October 16, 2017 at 8:00 am

    The Global Macrolide Antibiotics Market is segmented on the basis of drugs which includes azithromycin, clarithromycin, erythromycin, fidaxomicin, and telithromycin. Pune, India, October 16, 2017/MRFR Press Release/- Market Research Future published a ... […]

via Google News and Bing News

Other Interesting Posts

Leave a Reply

%d bloggers like this: