Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Research Study to Shed Light on Emerging Seaborne Pathogen

22.01.2009
A new research study at the University of Delaware seeks to determine why Vibrio parahaemolyticus, a microorganism that lives in seawater and is related to the bacterium that causes cholera, is expanding its range and virulence.

Vibrio parahaemolyticus is a leading cause of seafood-borne illness worldwide, most frequently associated with the consumption of raw or undercooked seafood, particularly oysters and other mollusks, and crabs. Victims typically suffer from diarrhea, vomiting, fever and chills for a few days, although the infection can be fatal in those with weakened immune systems.

“This organism has been around for a long time,” says Michelle Parent, assistant professor of medical technology at the University of Delaware and a co-investigator on the study. “However, only recently, in the past decade, has a new, more virulent isolate become more prevalent around the globe.”

In North America, Vibrio parahaemolyticus is considered an “emerging pathogen.” An estimated 4,500 cases of infection occur each year in the United States, according to the Centers for Disease Control. However, the agency suggests the number likely is much higher because labs rarely use the medium necessary to identify the organism, and cases go unreported.

“Vibrio parahaemolyticus usually causes a gastrointestinal infection that lasts two to three days, although individuals with compromised immune systems who work around seawater and get infected from a cut or open wound can die within a day,” Parent says.

“This organism grows super-fast,” Parent explains. “It has a replication time of six to nine minutes, which is very quick compared to other microbes.”

The ultimate aim of the University of Delaware study, which is funded by a $400,000 food biosafety grant from the U.S. Department of Agriculture (USDA), is to home in on this emerging pathogen's virulence genes and determine how the organism overcomes its victim's immune system -- information that can then be used to combat, detect and prevent infection.

The aquaculture industry loses millions of dollars each year due to the contamination of oyster beds with V. parahaemolyticus during the summer months. Thus, providing oyster farmers with an agent to treat the oysters is an important overall goal and potential future direction of the research, Parent says.

Working with Parent on the project are E. Fidelma Boyd, assistant professor of biological sciences at the University of Delaware, and collaborator Gary Richards, a research microbiologist at the USDA's Agricultural Research Service in Dover, Del.

“Vibrio parahaemolyticus is most prevalent in the warmer summer months, especially in the U.S. Gulf Coast region where it occurs in high numbers,” Boyd, a native of Ireland, says.

“In the past decade, the organism's geographic distribution has been extended into more northerly climes, in particular, the Pacific Northwest, most likely due to global warming. Thus, the occurrence and prevalence of the organism is likely to continue to expand,” Boyd notes.

An oyster filters its food from the seawater in which it lives, ingesting not only tiny plankton but whatever else may be present in the water, including harmful bacteria such as V. parahaemolyticus. Thus, when a person consumes a raw oyster contaminated with the organism, they become infected. (Thoroughly cooking the seafood can prevent infection.)

The researchers want to determine what happens once V. parahaemolyticus attaches to a host's cells and begins multiplying.

Through a series of experiments using various infectious doses of the organism, the scientists will explore what happens when a cell is infected, and what immune response is required to eliminate infection.

“Something is happening to allow this organism to predominate,” Parent says. “What makes it so powerful? Does it have some advantage in the environment?”

“We want to determine if the bacterium has acquired new genes to make it more virulent, allowing it to survive better in the aquatic environment and/or in the human gut,” Boyd adds.

In a recent study published in BMC Microbiology, Boyd, Parent and their co-authors show using genomic analysis that this new highly virulent strain has acquired large pieces of DNA, which may give the bacterium a major advantage from an evolutionary point of view.

“Using molecular genetic approaches, we will delete some of these genes in the bacterium and determine how well the organism can survive and grow,” Boyd notes.

Tracey Bryant | Newswise Science News
Further information:
http://www.udel.edu

More articles from Ecology, The Environment and Conservation:

nachricht Conservationists are sounding the alarm: parrots much more threatened than assumed
15.09.2017 | Justus-Liebig-Universität Gießen

nachricht A new indicator for marine ecosystem changes: the diatom/dinoflagellate index
21.08.2017 | Leibniz-Institut für Ostseeforschung Warnemünde

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: LaserTAB: More efficient and precise contacts thanks to human-robot collaboration

At the productronica trade fair in Munich this November, the Fraunhofer Institute for Laser Technology ILT will be presenting Laser-Based Tape-Automated Bonding, LaserTAB for short. The experts from Aachen will be demonstrating how new battery cells and power electronics can be micro-welded more efficiently and precisely than ever before thanks to new optics and robot support.

Fraunhofer ILT from Aachen relies on a clever combination of robotics and a laser scanner with new optics as well as process monitoring, which it has developed...

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

An international team of physicists a coherent amplification effect in laser excited dielectrics

25.09.2017 | Physics and Astronomy

LaserTAB: More efficient and precise contacts thanks to human-robot collaboration

25.09.2017 | Trade Fair News

Highest-energy cosmic rays have extragalactic origin

25.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>