HOME >> BIOLOGY >> NEWS
Food safety: French discovery explains how Listeria penetrates the body, and may suggest new drug delivery strategies

e to enter the bloodstream, where it disseminates to the central nervous system and the placenta. But, the molecular events that allow Listeria to cross the intestinal barrier have remained a mystery--until now.

In previous studies, Cossart and her colleagues--including Jean Louis Gaillard, Jerme Mengaud and Marc Lecuit--had shown that a protein on Listeria's surface called "internalin" interacts with a receptor, E-cadherin found on cultured cells derived from the intestine. Similar to a key-and-lock system, internalin interacts with E-cadherin to promote the entry of Listeria into intestinal cells. Listeria can then cross the intestine and pass into the bloodstream, scientists said.

Studying this mechanism in animals proved difficult, however, because rats and mice produce a form of cadherin that doesn't bind with internalin. Fortunately, guinea pigs generate a suitable version of the protein, making these animals a useful model for studying oral Listeria infection. The difference between the two forms of cadherin, Cossart explained, is a single amino acid in the 16th position of cadherin's molecular chain.

For their latest Science study, Lecuit et al.(Cossart's team in collaboration with transgenesis expert Charles Babinet and other scientists at the Pasteur Institute), investigated oral infection mechanisms within guinea pigs and transgenic mice, which had been genetically modified to express the human version of cadherin in the intestine. Animals received oral doses of both wild-type Listeria, as well as a mutant, internalin-free version of the bacterium. Wild Listeria, featuring the internalin protein, proved fatal in most cases, whereas the mutant strain caused no deaths and failed to cross the intestine and invade organ tissues.

Thus, the French investigation identifies a "virulence factor" or molecular mechanism by which Listeria causes disease, thereby addressing a key recommenda
'"/>

Contact: Ginger Pinholster
gpinhols@aaas.org
202-326-6421
American Association for the Advancement of Science
31-May-2001


Page: 1 2 3 4

Related biology news :

1. Bones from French cave show Neanderthals, Cro-Magnon hunted same prey
2. Fire on French Riviera
3. Smaller food portions may explain the French paradox of rich foods and a svelte population
4. ESA providing Kyoto estimates of French Guianas tropical forests
5. Researchers develop white wine with cholesterol-lowering benefits, discover Israeli wines healthier than French wines
6. Beyond the French paradox
7. Study seems to show why French suffer less heart disease, cancer
8. The Reason The French Have Low Levels Of Heart Disease
9. New Technology Turns French Fry Oil Into Diesel Fuel
10. French Researchers Breed Flightless Ladybirds As Pest-Killers
11. Very Fruitful Collaboration Between French And German Scientists Yields Unusual Insights Into The Structure Of Membrane Proteins

Post Your Comments:
(Date:4/17/2014)... trials to treat tuberculosis could be the basis for ... bacteria, fungal infections and parasites, yet evade resistance, according ... collaborators. , Led by U. of I. chemistry professor ... drug SQ109 attacks the tuberculosis bacterium, how the drug ... to malaria and how targeting multiple pathways reduces ...
(Date:4/17/2014)... West Orange, NJ. April 16, 2014. Kessler Foundation ... for $1.8 million from the Department of Defense ... PhD, is principal investigator for the randomized, double-blinded, ... to improve bone and muscle strength after spinal ... Human Performance & Engineering Research at Kessler Foundation. ...
(Date:4/17/2014)... Occurring in about one per eight hundred births, Down ... frequent genetic cause of intellectual disability. It results from ... a third copy of chromosome 21 (1% of the ... his team in the Department of Genetic Medicine and ... Medicine, published in Nature , shed light on ...
Breaking Biology News(10 mins):Multitarget TB drug could treat other diseases, evade resistance 2Kessler Foundation awarded Department of Defense grant for spinal cord injury research 2Trisomy 21: How an extra little chromosome throws the entire genome off balance 2Trisomy 21: How an extra little chromosome throws the entire genome off balance 3
(Date:1/15/2014)... A study has been launched to test ... track could help to tackle the problem of obesity.  This ... GP surgery based in Stowmarket) and academics at University Campus ... Telemetry technology, which is inspired by equipment used to collect ...
(Date:1/15/2014)... Two champions of science, technology, engineering, ... an annual competition for middle and high school students ... STEM study. The competition presents students with real-world problems ... Aptitude, Mathematics, and Sciences is a program administered ...
(Date:1/15/2014)... 15, 2014 DTS Language Services, Inc ... Web Portal for Life Science organizations who need document translations. ... subject matter of their documents in advance with a selection ... time-to-delivery of translations, often a critical factor in clinical and ...
(Date:1/15/2014)... Freeslate, Inc ., the leading ... Lupin Limited, one of India’s top five pharmaceutical companies, ... System for high throughput solid form screening. ... a wide range of quality, affordable generic and branded ...
Breaking Biology Technology:Formula 1 Technology Tackles Obesity in Unique Healthcare Partnership 2Formula 1 Technology Tackles Obesity in Unique Healthcare Partnership 3Formula 1 Technology Tackles Obesity in Unique Healthcare Partnership 4Technology Student Association Partners with Leaders in STEM Education Advocacy for Annual Competition 2Technology Student Association Partners with Leaders in STEM Education Advocacy for Annual Competition 3Technology Student Association Partners with Leaders in STEM Education Advocacy for Annual Competition 4Technology Student Association Partners with Leaders in STEM Education Advocacy for Annual Competition 5DTS Improves Efficiency for Life Science Document Translations 2Lupin Selects Freeslate’s CM Protégé PharmD System to Accelerate Polymorph Screening for Drug Development 2Lupin Selects Freeslate’s CM Protégé PharmD System to Accelerate Polymorph Screening for Drug Development 3
Cached News: