Navigation Links
Light, photosynthesis help bacteria invade fresh produce

Exposure to light and possibly photosynthesis itself could be helping disease-causing bacteria to be internalized by lettuce leaves, making them impervious to washing, according to research published in the October issue of the journal Applied and Environmental Microbiology.

Salmonella enterica is a common cause of foodborne gastroenteritis, with an estimated number of 1 to 3 million human cases per year in the United States. Fresh produce is increasingly being implicated as a source of infection. One of the largest foodborne outbreaks in recent history, the Salmonella St. Paul outbreak in 2008 which sickened over 1,400 people, was associated with tomatoes and jalapeno peppers.

Previous studies of foodborne pathogens on produce have found that the bacteria do not only attach to the surface of fresh produce but find their way below the surface of the skin through pores called stomata where they can hide from and resist washing and food sanitizers.

In the study, researchers from the Agricultural Research Organization at the Volcani Center in Israel and Tel-Aviv University examined the role that light and photosynthesis might play on the ability of salmonella bacteria to infiltrate lettuce leaves via stomata. Sterile iceberg lettuce leaves were exposed to bacteria either in the light, in the dark, or in the dark after 30 minutes of exposure to light. Incubation in the light or preexposure to light resulted in aggregation of bacteria around open stomata and invasion into the inner leaf tissue. In contrast, incubation in the dark resulted in a scattered attachment pattern and very little internalization.

The researchers believe that the increased propensity for internalization in the light may be due to several factors. First, in the absence of light plants enter a period of dormancy, where stomata are closed and no photosynthesis takes place. In the light, the stomata are open. Additional findings also suggest that the bacteria are attracted to the open stomata by the nutrients produced during photosynthesis which are not present in the dark.

"The elucidation of the mechanism by which Salmonella invades intact leaves has important implications for both pre- and postharvest handling of lettuce and probably other leafy vegetables. The capacity to inhibit internalization should limit bacterial colonization to the phylloplane and consequently might enhance the effectiveness of surface sanitizers," say the researchers.


Contact: Jim Sliwa
American Society for Microbiology

Related biology news :

1. Research project aims to control sunlight, extend growing season and conserve energy
2. The sky is not falling: Pollution in eastern China cuts light, useful rainfall
3. Researchers successfully simulate photosynthesis and design a better leaf
4. Discovering the secret code behind photosynthesis
5. Pliable proteins keep photosynthesis on the light path
6. Shuttle brings space-grown strep bacteria back for study
7. The worlds oldest bacteria
8. Bacteria from sponges make new pharmaceuticals
9. Boston University biomedical engineers find chink in bacterias armor
10. University of Leicester scientists discover technique to help friendly bacteria
11. Spaceflight shown to alter ability of bacteria to cause disease
Post Your Comments:
(Date:8/15/2017)... LLC , a medical device company focused on improving the safety ... ISO 13485 Certification, the global standard for medical device quality management ... ... for the early detection of IV infiltrations. ... "This is an important milestone for ivWatch, as it validates our ...
(Date:6/23/2017)... ITHACA, N.Y. , June 23, 2017 ... a leader in dairy research, today announced a new ... help reduce the chances that the global milk supply ... this dairy project, Cornell University has become the newest ... Food Supply Chain, a food safety initiative that includes ...
(Date:5/16/2017)... TEANECK, N.J. , May 16, 2017  Veratad ... leading provider of online age and identity verification solutions, ... the K(NO)W Identity Conference 2017, May 15 thru May ... Ronald Regan Building and International Trade Center. ... across the globe and in today,s quickly evolving digital ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... N.C. (PRWEB) , ... October 11, 2017 , ... ... ARCS® Foundation President Andi Purple announced Dr. Suneel I. Sheikh, the co-founder, ... ( ASTER Labs ), Inc. has been selected for membership in ARCS ...
(Date:10/11/2017)... ... ... is a basic first aid supply for any work environment, but most personal eye wash ... if a dangerous substance enters both eyes? It’s one less decision, and likely quicker response ... piece. , “Whether its dirt and debris, or an acid or alkali, getting anything in ...
(Date:10/11/2017)... ... October 11, 2017 , ... Proscia Inc ., ... a Webinar titled, “Pathology is going digital. Is your lab ready?” with Dr. ... best practices and how Proscia improves lab economics and realizes an increase in ...
(Date:10/11/2017)... and LAGUNA HILLS, Calif. , Oct. ... Cancer Research, London (ICR) and University ... SKY92, SkylineDx,s prognostic tool to risk-stratify patients with multiple myeloma ... MUK nine . The University of Leeds ... partly funded by Myeloma UK, and ICR will perform the ...
Breaking Biology Technology: