Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Honeybees harbor antibiotic-resistance genes

30.10.2012
Bacteria in the guts of honeybees are highly resistant to the antibiotic tetracycline, probably as a result of decades of preventive antibiotic use in domesticated hives.

Researchers from Yale University identified eight different tetracycline resistance genes among U.S. honeybees that were exposed to the antibiotic, but the genes were largely absent in bees from countries where such antibiotic use is banned. The study appears on October 30 in mBio®, the online open-access journal of the American Society for Microbiology.

"It [resistance] seems to be everywhere in the U.S.," says Nancy Moran of Yale University, a senior author on the study. "There's a pattern here, where the U.S. has these genes and the others don't."

Honeybees the world over are susceptible to the bacterial disease called "foulbrood", which can wipe out a hive faster than beekeepers can react to the infection. In the U.S., beekeepers have kept the disease at bay with regular preventive applications of the antibiotic oxytetracycline, a compound that closely resembles tetracycline, which is commonly used in humans. Oxytetracycline has been in use among beekeepers since the 1950s, and many genes that confer resistance to oxytetracycline also confer resistance to tetracycline.

Using sensitive molecular techniques, Moran and her colleagues screened honeybees from several locations in the United States and from Switzerland, the Czech Republic, and New Zealand as well as several wild bumblebees from the Czech Republic, for the presence and abundance of tetracycline resistance genes. They found that U.S. honeybees have greater numbers and a more diverse set of tetracycline resistance genes than honeybees from the other countries.

Moran says it is reasonable to expect to see widespread resistance among bees, considering the decades-long use of oxytetracycline in honeybee hives. "It seems likely this reflects a history of using oxytetracycline since the 1950s. It's not terribly surprising. It parallels findings in other domestic animals, like chickens and pigs," says Moran.

Moran notes that beekeepers have long used oxytetracycline to control the bacterium that causes foulbrood, but the pathogen eventually acquired resistance to tetracycline itself. Of the foulbrood pathogens Melissococcus pluton and Paenibacillus larvae, Moran says, "They carry tetL, which is one of the eight resistance genes we found. It's possible that the gene was transferred either from the gut bacteria to the pathogen or from the pathogen to the gut bacteria."

Switzerland, the Czech Republic, and New Zealand do not allow beekeepers to use oxytetracycline in hives, so it is perhaps predictable that honeybees and wild bumblebees from these countries harbored only two or three different resistance genes and only in very low copy numbers, suggesting that the bacteria did not require the genes very frequently.

The authors of the study point out that by encouraging resistance and altering the bacteria that live in honeybee guts, decades of antibiotic applications may have actually been detrimental to honeybee wellbeing. Studies have suggested that the bacterial residents of the honeybee gut play beneficial roles in neutralizing toxins in the bees' diet, nutrition, and in defending the bee against pathogens. By disrupting the honeybee microbiota and reducing its diversity, long-term antibiotic use could weaken honeybee resistance to other diseases. Hence, the treatment that was meant to prevent disease and strengthen the hive may actually weaken its ability to fight off other pathogens.

Moran says while the study is interesting from the perspective of honeybee health and could have implications for how honeybee diseases are managed, the presence of resistance genes in the honeybee gut doesn't pose a direct risk to humans. These gut bacteria, says Moran, "don't actually live in the honey, they live in the bee. We've never actually detected them in the honey. When people are eating honey, they're not eating these bacteria."

mBio® is an open access online journal published by the American Society for Microbiology to make microbiology research broadly accessible. The focus of the journal is on rapid publication of cutting-edge research spanning the entire spectrum of microbiology and related fields. It can be found online at http://mBio.asm.org.

The American Society for Microbiology is the largest single life science society, composed of over 39,000 scientists and health professionals. ASM's mission is to advance the microbiological sciences as a vehicle for understanding life processes and to apply and communicate this knowledge for the improvement of health and environmental and economic well-being worldwide.

Jim Sliwa | EurekAlert!
Further information:
http://www.asmusa.org
http://mBio.asm.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: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Researchers invent tiny, light-powered wires to modulate brain's electrical signals

21.02.2018 | Life Sciences

The “Holy Grail” of peptide chemistry: Making peptide active agents available orally

21.02.2018 | Life Sciences

Atomic structure of ultrasound material not what anyone expected

21.02.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>