Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UNC study finds protein in male reproductive tract kills bacteria, may improve fertility

06.05.2004


Scientists at the University of North Carolina at Chapel Hill have found that a protein they discovered three years ago in the male reproductive tract is a potent anti-bacterial agent.



In addition to protecting the male against invading bacteria, the protein may aid fertilization by protecting sperm from harmful organisms encountered in the female reproductive tract.

A report of the study, now online, will be published in the July issue of the journal Endocrinology. Designated DEFB118, the protein is found in the epididymis, a coiled duct through which sperm pass after leaving the testis. During passage through the epididymis, sperm become mature and acquire forward motility and fertilizing ability.


DEFB118 may be important in the innate immune system, said Dr. Susan H. Hall, associate professor of pediatrics in the UNC School of Medicine’s Laboratories for Reproductive Biology.

"Antibodies for protection may not be present when a pathogen comes in, so we need an innate defense system, something right there and ready to go," Hall added.

A wide variety of anti-microbial proteins in different classes have been identified in species as diverse as insects and humans. The most abundant antibiotic proteins in humans are the defensins. "This study demonstrates that the sperm-binding protein we discovered is an active defensin, one that has potent antibacterial activity," Hall said.

In humans, defensins are produced in the skin, eyes, nose, ears, mouth, digestive system, lungs and reproductive tract.

"When a pathogen tries to enter our bodies, defensins are ready and waiting there to kill them," Hall said. "And if the defensins are overpowered, then other protective mechanisms including antibodies are called in to finish the job."

Hall’s laboratory first reported the new sperm-binding defensin, identified by graduate student Liu Qiang, in 2001. The protein may be a broad-spectrum anti-microbial that attacks and destroys a variety of bacteria, said UNC postdoctoral researcher Dr. Suresh Yenuga, the new report’s lead author.

"This protein kills bacteria by disrupting their outer and inner cell membranes, resulting in the release of cell contents," he said. "In treating E. coli with different concentrations of DEFB118 over different time periods, we found it kills the bacteria within 15 minutes. Its anti-bacterial activity is dose-, time- and structure-dependent."

Study co-author and UNC postdoctoral researcher Dr. Yashwanth Radhakrishnan is exploring the evolutionary significance of defensin genes, how they evolved in the human genome. Numerous proteins similar in key attributes exist in different mammalian species, he said.

"We have already found homologues in monkeys, mouse and rat. The cluster of genes we’re studying is 100 million years old," he said. "Do they have multiple functions or the same function? Are there differences in their mechanisms of action? Across species, we still have no data on function, or on what species of bacteria or viruses they kill. We hope to find some answers."

The Laboratories for Reproductive Biology, established more than 30 years ago, includes faculty in the departments of biochemistry and biophysics, cell and developmental biology, genetics, cell and molecular physiology, obstetrics and gynecology, and pediatrics. The LRB promotes understanding of normal and abnormal reproductive functions to discover new methods of treating infertility and develop new methods of fertility control.


LRB research is supported by grants from the National Institute of Child Health and Human Development, the NIH Fogarty International Center, the Contraceptive Research and Development Program, the Andrew W. Mellon Foundation and the Specialized Cooperative Centers Program in Reproduction Research at the NIH.

Leslie H. Lang | UNC
Further information:
http://www.unc.edu/news/newsserv/archives/may04/lrb050504.html

More articles from Life Sciences:

nachricht Research team creates new possibilities for medicine and materials sciences
22.01.2018 | Humboldt-Universität zu Berlin

nachricht Saarland University bioinformaticians compute gene sequences inherited from each parent
22.01.2018 | Universität des Saarlandes

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Thanks for the memory: NIST takes a deep look at memristors

22.01.2018 | Materials Sciences

Radioactivity from oil and gas wastewater persists in Pennsylvania stream sediments

22.01.2018 | Earth Sciences

Saarland University bioinformaticians compute gene sequences inherited from each parent

22.01.2018 | Life Sciences

VideoLinks Wissenschaft & Forschung
Overview of more VideoLinks >>>