Navigation Links
Biofilms help Salmonella survive hostile conditions, Virginia Tech researchers say

Virginia Tech scientists have provided new evidence that biofilms bacteria that adhere to surfaces and build protective coatings are at work in the survival of the human pathogen Salmonella.

One out of every six Americans becomes ill from eating contaminated food each year, with over a million illnesses caused by Salmonella bacteria, according to the Centers for Disease Control and Prevention. Finding out what makes Salmonella resistant to antibacterial measures could help curb outbreaks.

Researchers affiliated with the Fralin Life Science Institute discovered that in addition to protecting Salmonella from heat-processing and sanitizers such as bleach, biofilms preserve the bacteria in extremely dry conditions, and again when the bacteria are subjected to normal digestive processes. The study is now online in the International Journal of Food Microbiology and will appear in the April issue.

"Biofilms are an increasing problem in food processing plants serving as a potential source of contamination," said Monica Ponder, an assistant professor of Food Science and Technology in the College of Agriculture and Life Sciences. "We have discovered that Salmonella in biofilms survive on dried foods much better than previously thought, and because of this are more likely to cause disease," Ponder said.

Outbreaks of Salmonella associated with dried foods such as nuts, cereals, spices, powdered milk and pet foods have been associated with over 900 illnesses in the last five years. These foods were previously thought to be safe because the dry nature of the product stops microbial growth.

"Most people expect to find Salmonella on raw meats but don't consider that it can survive on fruits, vegetables or dry products, which are not always cooked," Ponder said.

In moist conditions, Salmonella thrive and reproduce abundantly. If thrust into a dry environment, they cease to reproduce, but turn on genes which produce a biofilm, protecting them from the detrimental environment.

Researchers tested the resilience of the Salmonella biofilm by drying it and storing it in dry milk powder for up to 30 days. At various points it was tested in a simulated gastrointestinal system. Salmonella survived this long- term storage in large numbers but the biofilm Salmonella were more resilient than the free-floating cells treated to the same conditions.

The bacteria's stress response to the dry conditions also made it more likely to cause disease. Biofilms allowed the Salmonella to survive the harsh, acidic environment of the stomach, increasing its chances of reaching the intestines, where infection results in the symptoms associated with food poisoning.

This research may help shape Food and Drug Administration's regulations by highlighting the need for better sanitation and new strategies to reduce biofilm formation on equipment, thus hopefully decreasing the likelihood of another outbreak.


Contact: Lindsay Key
Virginia Tech

Related biology news :

1. LSUHSC scientist awarded nearly $2 million to determine role of biofilms in common fungal infection
2. Mechanisms involved in resistance to the bacteria Salmonella studied in a Ph.D. thesis
3. Assessing a new technique for ensuring fresh produce remains Salmonella-free
4. Salmonella infection, but not as we know it
5. UCSB researchers discover particularly dangerous Salmonella
6. UCSB researchers find a way to detect stealthy, hypervirulent Salmonella strains
7. UCI-led study uncovers how Salmonella avoids the bodys immune response
8. Cushion plants help other plants survive
9. Not just cars, but living organisms need antifreeze to survive
10. How do corals survive in the hottest reefs on the planet?
11. Collaring tapirs to help them survive
Post Your Comments:
(Date:11/30/2015)... Nov. 30, 2015  BIOCLAIM announced today that ... year,s Fierce Innovation Awards:  Healthcare Edition, an awards ... , FierceHealthcare , and ... finalist in the category of "Privacy and Cybersecurity." ... --> Photo - ...
(Date:11/26/2015)... Nov. 26, 2015 Research and Markets ( ... "Capacitive Fingerprint Sensors - Technology and Patent Infringement Risk ... --> --> Fingerprint sensors using ... smartphones. The fingerprint sensor vendor Idex forecasts an increase ... in mobile devices and of the fingerprint sensor market ...
(Date:11/20/2015)... NXTD ) ("NXT-ID" or the ... mobile commerce market and creator of the Wocket® smart ... recently interviewed on The RedChip Money Report ... on Bloomberg Europe , Bloomberg Asia, Bloomberg Australia, ... NXTD ) ("NXT-ID" or the "Company"), a biometric authentication ...
Breaking Biology News(10 mins):
(Date:11/30/2015)... ... ... Global Stem Cells Group announced that its scientific team is in ... stem cells. The announcement starts a new phase toward launching the simple, quick system ... the lipoaspirate obtained from liposuction of excess adipose tissue. , Lipoaspirate, contains a ...
(Date:11/30/2015)... Dec. 1, 2015 /PRNewswire/ - BioAmber Inc. (NYSE: BIOA ), ... joined the American Business Act on Climate Pledge, alongside more ... standing with the Obama Administration to demonstrate an ongoing commitment ... outcome to the COP21 Paris climate ... Sarnia, Canada . --> BioAmber ...
(Date:11/30/2015)... , Nov. 30, 2015 /PRNewswire/ - Zenith Epigenetics Corp. ... Dr. Norman C.W. Wong to its Board of ... comes to Zenith with a wealth of experience as co-founder ... molecular biology. --> --> ... Zenith Epigenetics, board of directors. Zenith,s long standing expertise in ...
(Date:11/30/2015)... Human Longevity, Inc. (HLI), the genomics-based, technology-driven ... Genomics, Inc., a leading genome informatics company offering highly ... The San Diego -based company has ... and Co-founder, Ashley Van Zeeland , Ph.D., who is ... of the deal were not disclosed. ...
Breaking Biology Technology: