Wellcome Research Round-Up 23/06/14

Our fortnightly round-up of stories from the Wellcome Trust research community…

Achilles’ heel in drug-resistant bacteria

A weakness in the outer membrane of bacteria has been identified by researchers at the University of East Anglia, suggesting a new method to disable bacteria and prevent antibiotic resistance.

In a study published in Nature, researchers show how gram negative bacteria cells transport ‘barrier building blocks’ called lipopolysaccharides, which make the bacteria particularly hard to penetrate, to their outer surface.

The team also discovered that if lipopolysaccharides are not able to get the bacteria’s outer membrane the bacteria become much more vulnerable and are easily killed.

Professor Changjiang Dong, Wellcome Trust Career Development Fellow, said: “We have identified the path and gate used by the bacteria to transport the barrier building blocks to the outer surface. Importantly, we have demonstrated that the bacteria would die if the gate is locked.”

“This is really important because drug-resistant bacteria are a global health problem. Many current antibiotics are becoming useless, causing hundreds of thousands of deaths each year. This research provides the platform for urgently-needed new generation drugs.”

The structure of the gram negative bacteria lipopolysaccharides was pinpointed using the intense light produced by the Diamond Light Source.

A tomato a day keeps the doctor at bay

A daily supplement of an extract found in tomatoes may improve the function of blood vessels, according to new research from Wellcome Trust-funded researchers the University of Cambridge.

Recent dietary studies suggest that a Mediterranean diet reduces the incidence of events related to the disease, including heart attack and stroke, in patients at high cardiovascular risk, or those who have previously had the disease.

One component of the Mediterranean diet thought to play a role in reducing this risk is lycopene, a powerful antioxidant which is ten times more potent than vitamin E and found in tomatoes and other fruits. In a study published in the journal PLOS One, researchers demonstrate one mechanism by which they believe lycopene reduces the risk.

They found that 7mg of oral lycopene supplementation improved and normalised endothelial function in the patients, but not in healthy volunteers. Lycopene improved the widening of the blood vessels by over a half (53%) compared to baseline in those taking the pill after correction for those who took the placebo; constriction of the blood vessels is one of the key factors that can lead to heart attack and stroke. However, the supplement had no effect on blood pressure, arterial stiffness or levels of lipids.

Bird flu ‘danger zones’ mapped

Scientists have mapped the “danger zones” in Asia which are vulnerable to the bird flu virus H7N9, which has infected 433 people (mainly in China) and killed 62.

In the study, published in Nature Communications, researchers from the Université Libre de Bruxelles (ULB), the International Livestock Research Institute (ILRI), Oxford University, and the Chinese Center of Disease Control and Prevention analyzed new data showing the distribution and density of live poultry markets in China and of poultry production overall in the country. Jeremy Farrar, Director of the Wellcome Trust was one of the study authors.

They found that the emergence and spread of the disease up until now is mainly linked to areas that have a high concentration of markets catering to a consumer preference for live birds and does not appear related to China’s growing number of intensive commercial poultry operations.

They have pinpointed areas elsewhere in Asia with similar conditions (places with a high density of live bird markets) that could allow H7N9 to significantly expand its range. Places at risk include urban areas in China where the disease has not yet occurred, along with large swaths of the Bengal regions of Bangladesh and India, the Mekong and Red River deltas in Vietnam, and isolated parts of Indonesia and the Philippines.

“We’re not saying these are areas where we expect to see infections emerge, but the concentration of bird markets makes them very suitable for infection should the virus be introduced there, and that knowledge could help guide efforts to limit transmission,” said Marius Gilbert, an expert in the epidemiology of livestock diseases at ULB and the paper’s lead author.

In other news…

Congratulations to Mat Fraser whose Cabinet of Curiosities (How Disability was Kept in a Box) won the Observer Ethical Award for Arts/Culture. Mat wrote this post for us about his project back in January.

Image credits: E.Coli David Gregory&Debbie Marshall, Wellcome Images, Tomatoes, Wellcome Library, London, Geographic distribution of predicted H7N9 infection risk from Predicting the risk of avian influenza A H7N9 infection in live-poultry markets across Asia