Pathogen grows on cold smoked salmon by using alternative metabolic pathways
2015-08-04
(Press-News.org) Washington, DC - August 4, 2015 - The pathogen, Listeria monocytogenes grows on refrigerated smoked salmon by way of different metabolic pathways from those it uses when growing on laboratory media. The research could lead to reduced incidences of food-borne illness and death, said principal investigator Teresa Bergholz, PhD. The research appears July 24 in Applied and Environmental Microbiology, a journal of the American Society for Microbiology.
In the study, the investigators showed that L. monocytogenes grows on cold smoked salmon by using different metabolic pathways to obtain energy from those it uses on laboratory media, even when the media was modified to have the same salt content and pH as the salmon. To grow on the salmon, the bacterium upregulates genes that enable it to use two compounds from cell membranes--ethanolamine and propanediol--as energy sources.
In an interesting parallel, L. monocytogenes, as well as Salmonella, is known to use those same genes to grow within a host--in the gastrointestinal tract, and on macrophages. "There may be ways we can use this information to control the pathogen both in foods as well as in infected people," said Bergholz, assistant professor in the Department of Veterinary and Microbiological Sciences at North Dakota State University, Fargo. "Understanding how a foodborne pathogen adapts to environmental stresses it encounters on a specific food could allow food microbiologists to develop inhibitors of metabolic or stress response pathways that are necessary for the pathogen to grow or survive on that product."
"The information may also enable improved risk assessments, as virulence of a pathogen may be affected considerably by the stress responses and/or metabolic pathways used to survive on the food," said Bergholz.
Bergholz noted that ready to eat products typically have very low levels of contamination with L. monocytogenes, and that the bacterium must be able to grow on the product during refrigerated storage in order to reach an infectious dose. "In many cases, the addition of organic acids will slow or stop the growth of this pathogen on ready to eat meats and seafood."
INFORMATION:
The sometimes fatal listeriosis primarily affects older adults, pregnant women, newborns, and people with compromised immune systems, according to the Centers for Disease Control and Prevention, which offers advice for prevention here: http://www.cdc.gov/listeria/prevention.html/.
This article can be found online at http://aem.asm.org/cgi/reprint/AEM.01752-15v1?ijkey=Ns.4LdwlNLHg.&keytype=ref&siteid=asmjournals.
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.
ELSE PRESS RELEASES FROM THIS DATE:
2015-08-04
Our nation's veterans continue to suffer emotional and psychological effects of war--some for decades. And while there has been greater attention directed recently toward post-traumatic stress disorder (PTSD), and more veterans are seeking help, current psychotherapy treatments are less than optimal, according to a new narrative review published in the August 4, 2015 issue of JAMA.
In a review of medical literature over a 35-year period, researchers from the Steven and Alexandra Cohen Center for Post-Traumatic Stress and Traumatic Brain Injury -- a program in the Department ...
2015-08-04
AURORA, Colo. (Aug. 4, 2015) - Physicians should improve the way they discuss firearm safety with patients by showing more respect for the viewpoints of gun owners, according to an article by a University of Colorado School of Medicine faculty member published in the Aug. 4 issue of JAMA.
Marian "Emmy" Betz, MD, MPH, associate professor of emergency medicine, and Garen J. Wintemute, MD, MPH, professor of emergency medicine at the University of California Davis, write that physician counseling about gun safety is a key component of preventing firearm injury and death. ...
2015-08-04
In a randomized trial that included veterans with posttraumatic stress disorder (PTSD), those who received mindfulness-based stress reduction therapy showed greater improvement in self-reported PTSD symptom severity, although the average improvement appears to have been modest, according to a study in the August 4 issue of JAMA, a violence/human rights theme issue.
Posttraumatic stress disorder affects 23 percent of veterans returning from Afghanistan and Iraq. Left untreated, PTSD is associated with high rates of other disorders, disability, and poor quality of life. ...
2015-08-04
Even though homicide and assault rates have decreased in the U.S. in recent years, the number of these and other types of violent acts remains high, according to a report in the August 4 issue of JAMA, a violence/human rights theme issue. The authors write that multiple strategies exist to improve interpersonal violence prevention efforts, and health care providers are an important part of this solution.
Interpersonal violence is a pervasive public health, social, and developmental threat that affects millions of U.S. residents each year. It is a leading cause of death ...
2015-08-04
A brief motivational intervention delivered during an emergency department visit did not improve outcomes for women with heavy drinking involved in abusive relationships, according to a study in the August 4 issue of JAMA, a violence/human rights theme issue.
There is a strong and reciprocal association between two highly prevalent public health problems: intimate partner violence (IPV) and heavy drinking. Each risk individually represents major costs to individuals, families, and society. The emergency department (ED) visit is conceptualized as a sensitive period or ...
2015-08-04
Screening women for partner violence and providing a resource list did not influence the number of hospitalizations, emergency department, or outpatient care visits compared with women only receiving a resource list or receiving no intervention over 3 years, according to a study in the August 4 issue of JAMA, a violence/human rights theme issue.
The U.S. Preventive Services Task Force recommends women of reproductive age be screened for partner violence. However, others, such as the World Health Organization conclude there is insufficient evidence for this recommendation. ...
2015-08-04
More than 1 in 4 female sex workers in the northern Mexico cities of Tijuana and Ciudad Juarez reported entering the sex trade as minors, and entering the sex trade as an adolescent vs as an adult was associated with a greater risk for HIV infection, according to a study in the August 4 issue of JAMA, a violence/human rights theme issue.
Adolescents migrating from Central America and Mexico to the United States are at risk for being trafficked into the sex industry in Mexico's northern border cities. Research from other regions indicates that those entering the sex trade ...
2015-08-04
Researchers at University of California, San Diego School of Medicine report that more than one in four female sex workers in two Mexican cities on the U.S. border entered the sex trade younger than age 18; one in eight before their 16th birthday. These women were more than three times more likely to become infected with HIV than those who started sex work as adults. They were also three times more likely to be violently coerced to engage in sex with male clients and seven times less likely to use a condom during their first month in the sex trade.
The study is published ...
2015-08-04
Scientists have discovered how earthworms can digest plant material, such as fallen leaves, that would defeat most other herbivores.
Earthworms are responsible for returning the carbon locked inside dead plant material back into the ground. They drag fallen leaves and other plant material down from the surface and eat them, enriching the soil, and they do this in spite of toxic chemicals produced by plants to deter herbivores.
The scientists, led by Dr Jake Bundy and Dr Manuel Liebeke from Imperial College London, have identified molecules in the earthworm gut that ...
2015-08-04
WASHINGTON, D.C., August 4, 2015 -- Terahertz radiation, the no-man's land of the electromagnetic spectrum, has long stymied researchers. Optical technologies can finagle light in the shorter-wavelength visible and infrared range, while electromagnetic techniques can manipulate longer-wavelength radiation like microwaves and radio waves. Terahertz radiation, on the other hand, lies in the gap between microwaves and infrared, whether neither traditional way to manipulate waves works effectively. As a result, creating coherent artificial sources of terahertz radiation in ...
LAST 30 PRESS RELEASES:
[Press-News.org] Pathogen grows on cold smoked salmon by using alternative metabolic pathways
