Viruses Can Turn Harmless E. Coli Dangerous....^_^

Viruses attacking E. coli, (electron microscopy picture). (Credit: Image courtesy of Norwegian School of Veterinary Science)

Bacteriophage Structure© Gary E. Kaiser

For her doctorate, Camilla Sekse studied how viral DNA can be transmitted from pathogenic to non-pathogenic E. coli. Viruses that infect bacteria in this way are called bacteriophages. Her findings reveal that such transmission of bateriophage between bacteria can occur, and that in the case of E. coli it can transform a harmless bacterium into one capable of causing disease in man.

Escherichia coli is a complex group of gut bacteria that are found in all warm-blooded animals and are for the most part harmless. A few, however, cause disease in man and animals. The E. coli bacteria that produce a poison called Shiga toxin can produce a range of effects in man. One common effect is bloody diarrhoea followed by complications such as kidney failure (haemolytic uraemic syndrome). The bacteria may be spread through contaminated food or water, or from contact with animals.

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A combination of qualities necessary to produce disease
A sequence of favourable circumstances needs to exist before E. coli can produce disease. The most important of these is the ability to produce Shiga toxin. The gene that codes for Shiga toxin is not innate, but is contained within bacteriophages. In other words, the bacterium needs first to be infected by a bacteriophage coding for Shiga toxin in order to produce the toxin itself.
In her work, Camilla Sekse studied E. coli O103:H25 bacteria isolated both from foodstuffs and patients from the E. coli outbreak of 2006. She and her colleagues discovered special features of these E. coli bacteria that separate them from ordinary, benign forms. This discovery lead to it being easier to demonstrate E. coli O103:H25 in suspect food products.

Dangerous bacteria in our environment
It seems that E. coli O103:H25 has existed in Norway for some time, since this bacterium was also found to be a cause of the kidney failure outbreaks both in 2003 and 2005. Studies of the entire genome of this bacterium have shown that it more closely resembles the enteropathogenic E. coli (bacteria that cause diarrhoea) than the more common, Shiga toxin-producing E. coli, namely E. coli O157:H7.
Escherichia coli bacteria that are not disease-causing can absorb and lose bacteriophages coding for Shiga toxin, and can be important in the spread of these bacteriophages in the environment, even though they don't themselves cause disease. It appears that some E. coli bacteria can both more easily absorb and lose bacteriophages that contain the gene for Shiga toxin, and this may well be the case for E. coli O103:H25.
The work was primarily carried out at the Department Food Safety & Environment of the Norwegian School of Veterinary Science. Parts of the study were done in close collaboration with scientists of the University of Barcelona and at the Technical University of Denmark in Copenhagen, and in co-operation with the Norwegian Institute of Public Health in Oslo. The project was financed by the Research Council of Norway and the Norwegian School of Veterinary Science.

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Minimizing The Spread Of Deadly Hendra Virus

This artificially coloured electron micrograph of Hendra virus is from the first identified case in Brisbane in 1994. (Credit: CSIRO)

CSIRO Livestock Industries' scientists working at the Australian Animal Health Laboratory (AAHL), in Geelong Victoria, have made a major breakthrough in better understanding how Hendra spreads from infected horses to other horses and humans.

Funded by the Australian Biosecurity CRC for Emerging Infectious Diseases, Dr Deb Middleton and her team at AAHL have defined the period following the first signs of disease when horses are most likely to shed Hendra virus and therefore infect other horses and people.
First identified in Brisbane in 1994, Hendra virus, which spreads from flying foxes, has regularly infected horses in Australia. Of the 11 equine outbreaks, four have led to human infection, with three of the six known human cases being fatal, the most recent of these in August 2008.
Dr Deb Middleton and her team at AAHL have defined the period following the first signs of disease when horses are most likely to shed Hendra virus and therefore infect other horses and people.

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Dr Middleton says limited information in the past, on when the disease can transmit, has made it difficult to manage infected horses to stop Hendra spreading further to people and other susceptible horses.
"Our research has also determined the best biological samples required for rapid diagnosis of the virus in horses and identified the important relationship between the period of highest transmission risk and the time with which the disease can easily be detected," Dr Middleton says.
As a result of these findings, veterinarians and horse owners are likely to consider the possibility of Hendra virus infection sooner when dealing with sick horses. This will mean appropriate management strategies can be put in place immediately, reducing the risk of spread while testing is being carried out.
"Unlike in horse flu, where apparently healthy horses can transmit the virus, horses in the early stages of Hendra infection generally appear to be at lower risk compared to animals with more advanced signs of illness."
These research findings will be used to update the guidelines that horse owners and vets use to handle potential Hendra virus infections.
Dr Middleton says her research also indicates there is an opportunity to diagnose Hendra virus in horses early, prior to advanced clinical signs and the highest risk of transmission.
"Developing a sensitive and specific stall-side test, which vets could use out in the field to diagnose the disease, has become even more important. However there are still key challenges to developing this type of advanced technology."
Although it is still not known how Hendra spreads from flying foxes to horses, Dr Middleton says the key to preventing human exposure and the exposure of additional horses is first understanding the disease in horses and secondly controlling the viral spread from diseased horses.
All research for the project was undertaken within AAHL's high-biocontainment facility.

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Climate Change Makes Migrations Longer For Birds

A team of scientists, led by Durham University, have published findings that show that the marathon flights undertaken by birds to spring breeding grounds in Europe, are going to turn into even more epic journeys; the length of some migrations could increase by as much as 250 miles.

The research team looked at the current migration patterns of European Sylvia warblers, a group of birds that are common residents and visitors to Europe, like the Blackcap. Published in the Journal of Biogeography, the scientists demonstrate evidence of potential breeding ranges shifting northwards in the future, while the wintering ranges remain stationary for many species.

The team used simulation models to see how climate change might affect warblers and found that climate change will have significant impacts, particularly on the projected migration distances for some of the long distance fliers.

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Some 500 million birds are estimated to migrate to Europe and Asia from Africa; birds as small as 9 grams undertake the annual migration of 1,000s of miles between the two continents to find food and suitable climate. Birds have to put on a large amount of weight as fat before migrating long distances; they even shrink the size of some of their internal organs to become more fuel efficient. Some species must double their weight to have enough energy to undertake the huge journeys. The first of these migrants are now starting to reappear once again in the UK countryside.
Team leader, Dr Stephen Willis of Durham University, said birds face an increasing fight to survive: “Most warblers come here in spring and summer time to take advantage of the surplus of insects, and leave for warmer climes in the autumn. From 2071 to 2100, nine out of the 17 species we looked at are projected to face longer migrations, particularly birds that cross the Sahara desert.
“Our findings show that marathon migrations for some birds are set to become even longer journeys. This is bad news for birds like the Whitethroat, a common farmland bird. The added distance is a considerable threat.”
Co-author of the research paper, Professor Rhys Green of Cambridge University and RSPB said: "These tiny birds make amazing journeys, pushing themselves to the limits of endurance. Anything that makes those journeys longer or more dependent on rare and vulnerable pit-stop habitats used for refuelling on migration could mean the difference between life and death.”
In terms of EU policy, the predicted effects of climate change on birds indicate a need for an appraisal of the designation of protected areas for migrant species, including key areas used for stopovers on long-distance migrations. The protection of bird species within the European Union is covered by legal directives that require member states to designate and protect Special Areas of Conservation (SACs) for habitats and Special Protection Areas (SPAs), the latter specifically designated to protect birds.
The research predicts that some species that fly long distances (on average 2,800 miles to 3,700 miles), are likely to face significantly longer flights, up to 250 miles longer, and shorter distance fliers may face journeys of up to 125 miles longer. Some birds cross the Mediterranean Sea and the Sahara in one go, whilst others pause to refuel in North Africa before crossing the desert. Night flying when the temperature is cooler is a technique that is also used by some of the long distance fliers.
Northern parts of the species’ ranges are expected to become of increasing importance and in some cases, species of northern populations are already thought to be exhibiting increases. Some birds might also be able to find new short distance routes. One common migrant, the Blackcap has already started spending winters in the UK.
Professor Rhys Green said: "These findings come as many people in the UK are enjoying the sights and sounds of their favourite birds returning after a winter in Africa. The challenges are large if we are to continue to see and hear these harbingers of the spring in anything like the numbers we are used to witnessing.
"We have already seen evidence that birds' ranges are moving north to track suitable climate conditions in the way predicted by past modelling. This latest research suggests they will face an increase in the length of an already arduous journey.”
Assuming increases in the fuel requirements for longer migrations can be physiologically accommodated by birds, they are likely to require more time for feeding prior to migration and/or additional stopovers to feed.
Nathalie Doswald, a student on the Durham team, said: “The projected distances for migrations would require long and short distance fliers to increase their fuel loads by 9 per cent and 5 per cent of lean body mass respectively. The predicted future temperature changes and the associated changes in habitat could have serious consequences for many species.”
Dr Willis said: “Some species may be able to adapt and change, for example by adopting shorter migration routes, if they can find enough food at the right time. Bird migrations are incredible feats of stamina and endurance but, as temperatures rise and habitats change, birds will face their biggest challenge since the Pleistocene era.”
Average migration distances – now and (in brackets) predicted for the future.
The four species with the largest predicted migration increases:
Subalpine Warbler – 1,615 miles (1,895-2,081miles) - Southern Europe to sub-Saharan Africa
Orphean Warbler – 1,679 miles (1,926-2,019 miles) - Southern Europe to sub-Saharan Africa
Barred Warbler – 2982 miles (3480-3,573 miles) - Central Europe to sub-Saharan Africa
Whitethroat – 3,417 miles (3,541-3,759 miles) – All Europe to sub-Saharan Africa
This research was funded by the Natural Environment Research Council and the RSPB.

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All Octopuses Are Venomous: Could Lead To Drug Discovery

Once thought to be only the realm of the blue-ringed octopus, researchers have now shown that all octopuses and cuttlefish, and some squid are venomous. The work indicates that they all share a common, ancient venomous ancestor and highlights new avenues for drug discovery.

Conducted by scientists from the University of Melbourne, University of Brussels and Museum Victoria, the study was published in the Journal of Molecular Evolution.
Dr Bryan Fry from the Department of Biochemistry at the Bio21 Institute, University of Melbourne said that while the blue-ringed octopus species remain the only group that aredangerous to humans, the other species have been quietly using their venom for predation, such as paralysing a clam into opening its shell.

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“Venoms are toxic proteins with specialised functions such as paralysing the nervous system” he said.
“We hope that by understanding the structure and mode of action of venom proteins we can benefit drug design for a range of conditions such as pain management, allergies and cancer.”
While many creatures have been examined as a basis for drug development, cephalopods (octopuses, cuttlefish and squid) remain an untapped resource and their venom may represent a unique class of compounds.
Dr Fry obtained tissue samples from cephalopods ranging from Hong Kong, the Coral Sea, the Great Barrier Reef and Antarctica.
The team then analysed the genes for venom production from the different species and found that a venomous ancestor produced one set of venom proteins, but over time additional proteins were added to the chemical arsenal.
The origin of these genes also sheds light on the fundamentals of evolution, presenting a prime example of convergent evolution where species independently develop similar traits.
The team will now work on understanding why very different types of venomous animals seem to consistently settle on the similar venom protein composition, and which physical or chemical properties make them predisposed to be useful as toxin.
“Not only will this allow us to understand how these animals have assembled their arsenals, but it will also allow us to better exploit them in the development of new drugs from venoms,” said Dr Fry.
“It does not seem a coincidence that some of the same protein types have been recruited for use as toxins across the animal kingdom.”

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New Orangutan Population Found in Indonesia

Conservationists discovered a new population of orangutans in a remote, mountainous corner of Indonesia — perhaps as many as 2,000 — giving a rare boost to one of the world's most endangered great apes.
A team surveying forests nestled between jagged, limestone cliffs on the eastern edge of Borneo island counted 219 orangutan nests, indicating a "substantial" number of the animals, said Erik Meijaard, a senior ecologist at the U.S.-based The Nature Conservancy.
"We can't say for sure how many," he said, but even the most cautious estimate would indicate "several hundred at least, maybe 1,000 or 2,000 even."

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The team also encountered an adult male, which angrily threw branches as they tried to take photos, and a mother and child.
There are an estimated 50,000 to 60,000 orangutans left in the wild, 90 percent of them in Indonesia and the rest in neighboring Malaysia.
The countries are the world's top producers of palm oil, used in food, cosmetics and to meet growing demands for "clean-burning" fuels in the U.S. and Europe. Rain forests, where the solitary animals spend almost all of their time, have been clear-cut and burned at alarming rates to make way for lucrative palm oil plantations.

The steep topography, poor soil and general inaccessibility of the rugged limestone mountains appear to have shielded the area from development, at least for now, said Meijaard. Its trees include those highly sought after for commercial timber.
Birute Mary Galdikas, a Canadian scientist who has spent nearly four decades studying orangutans in the wild, said most of the remaining populations are small and scattered, which make them especially vulnerable to extinction.
"So yes, finding a population that science did not know about is significant, especially one of this size," she said, noting that those found on the eastern part of the island represent a rare subspecies, the black Borneon orangutan, or Pongo pygmaeus morio.
The 700-square mile (2,500-square kilometer) jungle escaped the massive fires that devastated almost all of the surrounding forests in the late 1990s. The blazes were set by plantation owners and small-scale farmers and exacerbated by the El Nino droughts.
Nardiyono, who headed The Nature Conservancy's weeklong survey in December, said "it could be the density is very high because after the fires, the orangutans all flocked to one small area."
It was unusual to come face-to-face with even one of the elusive creatures in the wild and to encounter three was extraordinary, he said, adding that before this expedition, he had seen just five in as many years.
Conservationists say the most immediate next step will be working with local authorities to protect the area and others that fall outside of national parks. A previously undiscovered population of several hundred also was found recently on Sumatra island, home to around 7,000.
"That we are still finding new populations indicates that we still have a chance to save this animal," said Paul Hartman, who heads the U.S.-funded Orangutan Conservation Service Program, adding it's not all "gloom and doom."
Noviar Andayani, head of the Indonesian Primate Association and Orangutan Forum, said the new discoveries point to how much work still needs to be done to come up with accurate population assessments, considered vital to determining a species' vulnerability to extinction.
"There are many areas that still have not been surveyed," she said, adding that 18 private conservation groups have just started work on an in-depth census based on interviews with people who spend time in the forests.
They include villagers and those working on plantations or within logging concessions.
"We hope this will help fill in a few more gaps," said Andayani, adding that preliminary tests in areas where populations are known indicate that the new interview-based technique could provide a clearer picture than nest tallies.
"Right now the information and data we have about orangutans is still pretty rudimentary," she said.
Some experts say at the current rate of habitat destruction, the animals could be wiped out within the next two decades.

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