Corporate Banner
Satellite Banner
Food & Beverage Analysis
Scientific Community
 
Become a Member | Sign in
Home>News>This Article
  News
Return

Salmonella Relies on Single Food Source to Stay Potent

Published: Saturday, July 12, 2014
Last Updated: Wednesday, July 23, 2014
Bookmark and Share
Study suggests genes needed for nutrient could be attractive drug target to fight infection.

Scientists have identified a potential Achilles’ heel for Salmonella – the bacteria’s reliance on a single food source to remain fit in the inflamed intestine.

When these wily bugs can’t access this nutrient, they become 1,000 times less effective at sustaining disease than when they’re fully nourished.

The research suggests that blocking activation of one of five genes that transport the nutrient toSalmonella cells could be a new strategy to fight infection.

“For some reason, Salmonella really wants this nutrient, and if it can’t get this one, it’s in really bad shape,” said Brian Ahmer, associate professor of microbial infection and immunity at The Ohio State University and lead author of the study. “If you could block Salmonella from getting that nutrient, you’d really stopSalmonella.”

The research is published in the journal PLOS Pathogens.

Generally, most of the 42,000 Americans who report Salmonella infection annually ride out the gastroenteritis symptoms of diarrhea, fever, stomach cramps and vomiting for four to seven days, according to the Centers for Disease Control and Prevention. Antibiotics aren’t a recommended treatment for most infections because they kill good gut bacteria along with Salmonella.

The nutrient needed by Salmonella is composed of a sugar and amino acid stuck together, and is called fructose-asparagine. Its identification alone is also unusual: “It has never been discovered to be a nutrient for any organism,” Ahmer said.

Ahmer and colleagues found this important food source by first identifying the genes that Salmonellarequires to stay alive during the active phase of gastroenteritis, when the inflamed gut produces symptoms of infection.

Using a genetic screening technique, the researchers found a cluster of five genes that had to be expressed to keep Salmonella from losing its fitness during gastroenteritis. They then determined that those vital genes work together to transport a nutrient into the bacterial cell and chop up the nutrient so it can be used as food.

The study refers to the pathogen’s fitness because it’s an all-encompassing word for Salmonellasurvival, growth and ability to inflict damage.

Identifying the nutrient that the genes acted upon was a bit tricky and involved some guessing, Ahmer said. The team realized that the Salmonella genes they found resembled genes in other bacteria with a similar function – transporting the nutrient fructose-lysine into E. coli. But seeing a difference between the genes, the researchers landed, with some luck, on fructose-asparagine.

The researchers ran numerous experiments in cell cultures and mice to observe what happened to Salmonella in the inflamed gut when these genes were mutated. Under differing conditions,Salmonella’s fitness dropped between 100- and 10,000-fold if it could not access fructose-asparagine, even if all of its other food sources were available.

“That was one of the big surprises: that there is only one nutrient source that is so important toSalmonella. For most bacteria, if we get rid of one nutrient acquisition system, they continue to grow on other nutrients,” Ahmer said. “In the gut, Salmonella can obtain hundreds of different nutrients. But without fructose-asparagine, it’s really unfit.”

Because of that sole source for survival, the genes needed for acquisition of this nutrient could be effective drug targets.

“Nobody’s ever looked at nutrient transporters as drug targets because it’s assumed that there will be hundreds more transporters, so it’s a pointless pursuit,” Ahmer said.

This kind of drug also holds promise because it would affect only Salmonella and leave the trillions of other microbes in the gut unaffected.

Ahmer and colleagues are continuing this work to address remaining questions, including the window of time in which access to the nutrient is most important for Salmonella’s survival as well as identifying human foods that contain high concentrations of fructose-asparagine.

This work was supported by grants from the National Institute of Allergy and Infectious Diseases and the National Institute of General Medical Sciences.


Further Information
Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 2,500+ scientific posters on ePosters
  • More than 3,700+ scientific videos on LabTube
  • 35 community eNewsletters


Sign In



Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into TechnologyNetworks.com you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.


Scientific News
Decrease in Foodborne Outbreaks in Denmark
Almost every other registered salmonella infection in Denmark in 2014 was brought back by Danes travelling overseas.
How Safe Is Your Ground Beef?
If you don’t know how the ground beef you eat was raised, you may be putting yourself at higher risk of illness from dangerous bacteria. You okay with that?
Sweeteners Detected in Human Breast Milk
New data show that multiple types of NNS can be passed to nursing infants.
Food Science Team Finds Key to Tasty, Salt-Reduced Bread
Three food science researchers at the University of Alberta have discovered how to reduce salt in bread by half without compromising its taste or texture.
Yorkshire Scientists Could Hold Key to Preventing Future Horsemeat Scandals
Incidents like the horse meat scandal, which caused extensive damage to the UK’s farming and retail industry, could be consigned to the past thanks to revolutionary technology developed in the UK.
Detecting Hidden Ingredients
Researchers from China have used mass spectrometry to reveal the use of undeclared substances in dietary supplements.
Study Questions Presence in Blood of Heart-Healthy Molecules from Fish Oil Supplements
A new study from the Perelman School of Medicine at the University of Pennsylvania questions the relevance of fish oil-derived SPMs and their purported anti-inflammatory effects in humans.
How To Keep Your Rice Arsenic-Free
Researchers at Queen’s University Belfast have made a breakthrough in discovering how to lower worrying levels of arsenic in rice that is eaten all over the world.
Pesticide Found in 70 Percent of Massachusetts’ Honey Samples
New Harvard University study says that the pesticide commonly found in honey samples is implicated in Colony Collapse Disorder.
Printed "Smart Cap" Detects Spoiled Food
It might not be long before consumers can just hit “print” to create an electronic circuit or wireless sensor in the comfort of their homes.
SELECTBIO

Skyscraper Banner
Go to LabTube
Go to eposters
 
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
2,500+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
3,700+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FREE!