which could reflect the heavy load of microbes she carries in her four-chambered stomach.
Those bacteria are needed to break down grass and other delicacies in her fibrous diet but could also pose an infection risk.
Nature Newspublic-health experts are warning that a lack of surveillance may be allowing the 2009 pandemic H1n1 flu virus to go undetected in pigs.
The avian H5n1 flu virus leads to serious disease in poultry and causes huge economic losses,
the three most common endemic strains are H1n1, H1n2 and H3n2. Most expected that any new pandemic would involve the introduction of a viral subtype not previously seen in humans,
The emergence of the reassorted H1n1 pandemic virus which current research indicates noone has any immunity to, apart, perhaps,
and swine forms of H1n1 shared a common ancestor years before 1918. But he remains unconvinced by the series of genetic swaps proposed by the paper.
the pandemic H1n1 (swine flu virus currently circling the globe bears an uncanny resemblance to an influenza virus that wreaked havoc nearly a century ago,
Insects can become resistant to individual insecticides in much the same way as bacteria develop resistance to antibiotics.
One of the most common'pyramided'crops on the market is cotton that produces two different'Bt'toxins made naturally by the bacterium Bacillus thuringensis.
People infected with the H1n1 swine flu virus who are otherwise healthy should not routinely be given antiviral drugs,
where oseltamivir (Tamiflu) is given routinely out to all those suspected of having contracted H1n1. Although those with uncomplicated illness should not get oseltamivir or zanamivir (Relenza),
meaning that methane is produced by microbes underwater as they help to decay any flooded organic matter.
and Extension Center in Columbia, could help farmers to control crop pests by luring natural parasites or predators.
and infested the plots with rootworm before releasing around 600,000 nematode parasites. Root damage by rootworm larvae was less in the transgenic maize,
Proprietary bacteria then ingest the gases and produce ethanol says chief marketing officer Wesley Bolsen.
claims to have engineered microorganisms whose enzymes can break cellulose down into simple sugars and immediately convert those into ethanol.
An international team has sequenced the DNA of the microorganism that was to blame. Phytophthora infestans, the water mould that causes late blight in potatoes,
For microbes 25%is a lot, says Nusbaum. The variability of these regions suggest that they are quickly evolving,
and gasoline-producing bacterial reactors to new methods for making light-emitting diodes and synthetic enzymes for capturing carbon dioxide from industrial emissions.
The US government should grade microorganisms and toxins according to their risk as potential biothreat agents,
Research has shown how dirty piglets obtain'friendly'bacteria that help them to develop healthy immune systems later in life.
They also indicate that manipulating gut bacteria early in life might reduce allergies and other autoimmune diseases, says Denise Kelly, a gut immunologist at the University of Aberdeen, UK and one of the study's authors.
The study found that 90%of bacteria in the guts of the outdoor piglets came from the phylum Firmicutes.
Most of these were known lactobacillaceae for their health-promoting effects, and for their ability to limit intestinal pathogens such as Escherichia coli and Salmonella.
In contrast, the Firmicutes bacteria made up less than 70%and just more than 50%of the gut flora in indoor and isolated bred pigs respectively.
The pigs also had much smaller proportions of bacteria from the lactobacillaceae family. The team also found that the differences in gut microbial communities affected the expression of genes associated with the piglets'immune system.
Animals raised in the isolated environment expressed more genes involved in inflammatory immune responses and cholesterol synthesis,
which handles samples of H1n1 pandemic flu, and which earlier this year lost track of 22 vials containing harmless Ebola-virus genetic material.
Tracking systems for the most dangerous pathogens are more rigorous but could still be improved, the audit found.
This includes building a processing plant to produce an experimental biological control agent, a nucleopolyhedrovirus,
is caused by a morbillivirus a group of viruses that also includes measles. Clinical signs include fever, discharges from the eyes and nose, diarrhoea and dehydration.
The disease is caused by a virus called a morbillivirus a group that also includes the measles virus. Clinical signs include fever, discharges from the eyes and nose,
according to research showing that dirty piglets pick up'friendly'bacteria that help them to develop robust immune systems later in life.
which suggests that a lack of exposure to microbes in early life can affect development of the immune system and increase susceptibility to certain disorders, such as allergies and inflammatory bowel disease.
says that the results provide the first direct link between early exposure to microbes, immune health and gene expression (I e.
The study found that 90%of bacteria in the guts of the outdoor piglets came from the phylum Firmicutes.
Most of these were Lactobacillaceae, a family of bacteria known for their ability to limit intestinal pathogens such as Escherichia coli and Salmonella species. By contrast,
Firmicutes made up less than 70%of the gut flora in indoor pigs and slightly more than 50%of that in isolated pigs.
Pigs from these cleaner environments also had much smaller proportions of bacteria from the Lactobacillaceae.
Kelly's team also found that the differences in gut microbes affected the expression of genes associated with the piglets'immune systems.
patients with Crohn's also have reduced overall bacterial diversity, similar to the outdoor pigs, suggesting that the results might not extrapolate directly to human disease.
and the similarities between the microorganisms found in their guts, makes pigs good model animals for such studies.
Altered microbe makes biofuel: Nature Newsin a bid to overcome the drawbacks of existing biofuels,
researchers have engineered a bacterium that can convert a form of raw plant biomass directly into clean, road-ready diesel.
a modified Escherichia coli bacterium that can make biodiesel directly from sugars or hemicellulose, a component of plant fibre (see page 559).
and then short-circuited E coli's internal machinery for producing large fatty-acid molecules, enabling them to convert precursor molecules directly into fuels and other chemicals.
The team then inserted genes from other bacteria to produce enzymes able to break down hemicellulose.
such as analysis tracing mailed Bacillus anthracis spores back to a single-spore batch in Ivins's lab at the US ARMY Medical Research Institute of Infectious diseases in Fort Detrick, Maryland.
The crop carries a gene from the bacterium Bacillus thuringiensis (Bt), and was developed by Mahyco-Monsanto Biotech, a joint venture between the Jalna-based Maharashtra Hybrid Seed Company and the US seed giant Monsanto,
and not by microbes native to the region in which the truffle grows, as many researchers had thought.
Environmental groups and some countries have had longstanding concerns about the risk of genes spreading from crops to bacteria and increasing bacterial antibiotic resistance.
and concluded that the risk of transfer of antibiotic resistance from plants to bacteria was remote,
and that bacteria resistant to the antibiotics were already present in soil, animals and humans.
Q fever, caused by Coxiella burnetii bacteria, is harboured in mammals, birds and even insects. It can trigger abortions in goats and sheep and causes flu-like symptoms and sometimes pneumonia in humans.
cut down on the amount of bacteria in the goats'milk and afterbirth during lambing season the following year1.
whether one fast-spreading strain of the bacteria is causing human cases of the disease.
The french agricultural research institute, will start by looking at how the bacteria spreads in mice.
from understanding how the bacteria are distributed at such a large scale to correlating measurements of BACTERIAL DNA levels in bulk milk tank samples with infection rates.
Soil bacteria could yield drug to treat roundworm: Nature Newsa bacterial protein used in a common pesticide kills intestinal parasitic roundworms in mice
and may become a treatment option for humans, researchers say. Intestinal roundworms, including hookworms and whipworms, infect well over one billion people, lowering immune systems for HIV, malaria and tuberculosis and debilitating both physically and cognitively.
The new approach, published today in PLOS Neglected Tropical Diseases1, uses crystal proteins from the soil bacterium Bacillus thuringiensis (Bt.
This bacterium is a natural soil predator of nematodes, says author Raffi Aroian from the University of California,
San diego. The bacterium can kill the worm, he adds, and it has a great track record for safety around vertebrates.
Hookworms and some other parasitic nematodes have shown signs of resistance to albendazole, the current treatment approved by the World health organization.
The researchers orally infected mice and waited for the parasites to mature and become reproductively active adults before treating the mice with the crystal protein.
A few days after treatment, the mice had 98%fewer parasite eggs in their faecal samples
and 70%fewer adult parasites in their intestines compared to untreated mice. Aroian's previous study2 using a type of human intestinal roundworm parasite to infect hamsters showed a 90%reduction in three doses of Bt.
Taken together the two in vivo studies have shown significant therapeutic activity of a crystal protein against two species of nematode,
which are engineered to produce pest-killing toxins from the bacterium Bacillus thuringiensis, use less insecticide. Increased planting of herbicide-tolerant crops may also have reduced the use of many herbicides that linger in soil and waterways
When the International Census of Marine Microbes (ICOMM) kicked off in 2003 microbiologists had identified 6,
000 kinds of microbe and predicted that they might find as many as 600,000. But the latest analyses indicate that the oceans are home to at least 20 million types,
In 1997, the Chinese government approved the commercial cultivation of cotton plants genetically modified to produce a toxin from the bacteria Bacillus thuringiensis (Bt) that is deadly to the bollworm Helicoverpa armigera.
The bacteria Bacillus thuringiensis israelensis (Bti) is now the most commonly used microbicide to control mosquitoes worldwide
Ross River or chikungunya viruses. About 10 days later, they captured more than 90 mosquitoes, placed each one in a separate vial
The World health organization (WHO) announced on 10 august that the world is no longer experiencing an H1n1 influenza virus pandemic.
and that H1n1 would probably take on the behaviour of a seasonal flu virus. Margaret Chan,
a variety of aubergine modified to produce a protein from the Bacillus thuringiensis (Bt) bacterium that is toxic to insect pests.
In ongoing experiments, Hawlena is getting intriguing results by looking at the different kinds of soil bacteria that thrive on stressed or unstressed grasshopper corpses.
whether the physiological effects of stress on grasshoppers scale up to plants, soil, bacteria and onwards,
Nature Newsscientists in Uganda will next week start field trials of a banana variety genetically engineered to resist a bacterial disease that has been decimating crops across Central africa.
The bananas have a gene from green pepper to protect against banana Xanthomonas wilt (BXW which costs farmers in Africa's Great lakes region an estimated half a billion dollars every year.
and analyse whether the breed affects the composition of microorganisms in the soil. These plants will grow side by side with another GM banana variety developed at the laboratory,
A related parasite has been implicated in the well-known decline of honeybees, although the two events seem to be unconnected,
) The Primate Research Institute of Kyoto University reported on its website on 11 november that the culprit was simian retrovirus-4 (SRV-4). The problem emerged
The crops produce a toxin that is made naturally by the bacterium Bacillus thuringiensis called Bt toxin.
coaxing digesting bacteria to work harder and longer and to produce new hydrocarbon products. It's not a lack of interest or a lack of feedstock or anything like that,
when hives are invaded by predators or parasites, when apiculturists transport colonies over long distances, or as an everyday consequence of the busy nature of hives.
or funguslike microorganism, that destroys both the tuber and its leaves continues to be a major problem for farmers.
caused by the bacterium Coxiella burnetii, can trigger abortions in goats and sheep and cause flu-like symptoms and sometimes pneumonia in humans.
Nature Newsa slime mould long thought to hunt bacteria as prey turns out to have unexpected abilities: according to researchers in Texas, some of the amoebae are actually farmers,
husbanding their bacterial'crops'much as some ant species farm fungus. As social amoebae, slime moulds are bizarre creatures that live as individual singled-celled organisms while feeding,
But now, a selection of the soil-dwelling species Dictyostelium discoideum have been shown to husband their bacterial food source.
By prudently harvesting the bacteria and then migrating with them, the amoebae are seed able to a new food source at their destination.
shows that this'bacterial husbandry'is similar to the behaviour of other social animals, such as fungus-farming ants although compared to the ants,
It was thought previously that slime moulds were strictly predators of bacteria, forming the multicellular slug when scant food supplies prompted a move to new hunting grounds.
and noticed that some of these seemed to have bacteria in their reproductive structures, alongside their spores.
The team showed that the bacteria carried by the amoebae had the potential to initiate new populations in the lab,
The researchers dubbed the bacteria-carrying amoebae, which made up one-third of all clones in the wild population,'
If they then end up in an area that lacks sufficient edible bacteria, they can rely on their own supply to seed a new population for harvest.
Dictyostelium farmers seem sometimes to benefit from their husbandry skills even in natural soil that harbours a variety of bacteria,
because they can bring along bacteria of their choice, just as humans plant seeds in areas with naturally growing vegetation.
When the researchers compared the success of the farmers and non-farmers in areas of abundant edible bacteria
However, it would be interesting to know to what extent they allow the bacteria to proliferate at the new location.
The H5n1 strain of influenza which raged through Southeast asia a decade ago and has killed hundreds of people to date remains a problem in some developing countries,
The birds carry a genetic tweak that diverts an enzyme crucial for transmitting the H5n1 strain.
H5n1 is endemic in at least five countries, and is particularly threatening in Egypt and Indonesia, says Capua.
H5n1 outbreaks are controlled by swiftly culling the animals. In poor countries, however, there are lots of small farms,
Instead, developing countries try to control H5n1 by vaccinating birds. This doesn't prevent them from silently acquiring mild forms of the disease and
The researchers infected decoy-carrying birds with H5n1 and housed them with uninfected birds, some with the transgene and some without.
The technique may become most useful not for preventing the spread of H5n1 but for using similar cassettes to create resistance to other common poultry diseases.
Business Biofuel offering Gevo, a company that genetically modifies microbes to produce chemicals from plant sugars,
some of the most damaging diseases are Rift valley fever (Phlebovirus), which can sometimes cause a haemorrhagic fever,
and Bluetongue disease (Orbivirus). Whereas rich nations are controlling livestock diseases effectively, developing countries, including many in Africa
Goulding and his team are studying the soil microbes that convert nitrogen (from nitrogen-based fertilizers) into nitrous oxide,
In particular, they hope to manage the microbes, or their genes, so that less nitrogen is lost from the soil.
including viruses, bacteria and fungi some novel that, alone or in combination, might push a bee colony into precipitous decline.
other parasites, such as the Varroa mite (Varroa destructor), which spreads harmful viruses, continue to take their toll.
but how are they surviving against this onslaught of parasites, he says. The genome offers a window into the bees'immune pathways,
The pathogens include bacteria and viruses that cause smallpox, the plague, anthrax, Ebola and foot-and-mouth disease.
Nature Newswomen, beansprouts, cucumbers, bacteria, cows: the cast of the current European Escherichia coli outbreak is already a crowd.
Enter the phage. Bacteriophages are viruses that infect bacteria, and they are star players in the chain of events that led to this outbreak.
Bacterial infections often originate from contaminated food, but it is now about six weeks since the start of this outbreak and the trail is going cold.
It's hard to be sure of the culprit but this simply serves to highlight the importance of understanding how infectious bacteria get into the food chain in the first place.
Case-control studies of patients in the German outbreak pointed to salad vegetables and both cucumbers and beansprouts have been suspects.
It is possible that the vegetables were contaminated with bacteria originally carried in soil or water;
but the more likely source of the bacteria is animals. Pathogenic E coli are passed typically to humans from ruminant animals (cows or sheep) via faecal contamination in the food chain or through consumption of raw milk or meat products.
But how do pathogenic E coli arise in the first place? This is where bacteriophage come in. The bacterium in this outbreak, currently recognised as strain O104:
H4, makes Shiga toxin, which is responsible for the severe diarrhoea and kidney damage in patients
whose E coli infections develop into haemolytic uremic syndrome (HUS). The genes for the Shiga toxin are not actually bacterial genes,
but phage genes being expressed by infected bacteria. So when an E coli bacterium gets infected with a Shiga-toxin-producing phage,
it becomes pathogenic to humans. Our use of antibiotics may be helping those viral genes to spread.
If bacteria are exposed to some types of antibiotics they undergo what is called the SOS response,
which induces the phage to start replicating. Active replication of the phage causes the bacterial cells to burst open,
which releases the phage. It also releases the toxin, which is why antibiotics are used not usually to treat E coli infections (see'Europe's E coli outbreak:
time for the antibiotics?'.'One of the many unusual characteristics of strain O104: H4 is that it has resistance genes to multiple classes of antibiotics.
This suggests that wherever the bacteria have come from there has been selective pressure to resist antibiotics.
Heather Allison, a microbiologist at the University of Liverpool, UK, and David Acheson, a managing director for food safety at consulting firm Leavitt Partners in WASHINGTON DC, agree it is plausible that exposure to antibiotics in agricultural use
or in the environment might be enhancing the spread of Shiga-toxin-producing phage. Acheson worked on this question
Massachusetts, studying the molecular pathogenesis of Shiga-toxin-producing E coli in the 1990s. He says they saw Shiga-toxin-producing phage transfer between E coli in response to sub-therapeutic levels of the antibiotic ciprofloxacin in vitro and in the intestines of mice.
They do it in the laboratory, he says, but it's hard to show it happens in the environment.
from the European Reference Laboratory for verotoxin-producing E coli in Rome, Italy (verotoxin is another name for Shiga toxin).
And the gut is one place in which the phage move between different bacteria, and new pathogenic bacterial strains emerge.
Shiga toxins have been causing diarrhoeal disease in humans for centuries the bacterial genus Shigella and the Shiga toxins were named first for Kiyoshi Shiga,
a Japanese medical doctor who identified the bacterium during an outbreak of dysentery in Japan in 1897.
According to Allison, Shiga-toxin producing phage probably picked up the genes encoding Shiga toxin from these bacteria,
and since the 1980s have been spreading these virulent genes to other bacteria, including many strains of E coli.
We are seeing more and more Shiga-toxin-producing strains says Alison Weiss, microbiologist at the University of Cincinnati in Ohio.
How have Shiga-toxin-producing phage spread so widely in just a few decades? Allison says they have unusual characteristics that make them very successful.
They infect bacteria by binding to a protein called Bama on the surface of many bacterial cells,
Weiss adds that carrying the phage also provides a survival advantage for the host bacteria.
Once the bacteria are out in the environment say in manure they are fed on by other microbes
The toxins kill the other microbes, giving these bacteria an advantage. Not only are more E coli strains being infected with Shiga toxin,
but it seems to be moving into different classes of bacteria. The genome of strain O104:
H4 has been sequenced, and it shares many genes with enteroaggerative E coli (EAEC) strains. EAEC strains are associated not typically with zoonotic infections,
and EAEC and Shiga toxin is a very unusual combination, says Caprioli. This increased movement of Shiga-toxin-producing phage means that even more unusual and dangerous strains could be on the horizon.
Sustainable management of tropical forests has a long way to go: Nature Newsless than 10%of permanent tropical forests are under a sustainable management plan,
German E coli outbreak caused by previously unknown strain: Nature Newsthe bacterium responsible for the current outbreak of enterohaemorrhagic Escherichia coli (EHEC) infections in Germany is a strain that has never before been isolated in humans.
The discovery, announced today by the food safety office of the World health organization (WHO) in Geneva, Switzerland,
Scientists in Germany are feverishly analysing the genome sequence of the bacterium, and have found clues as to how this strain
The bacteria are relatively unusual in that they produce extended-spectrum à Â-lactamases enzymes that render the bacteria resistant to many different antibiotics.
Patients with E coli infections are treated not typically with antibiotics anyway, because the bacteria are thought to respond to the medication by increasing production of the Shiga toxin,
which can lead to the life-threatening complication haemolytic-uremic syndrome. But antibiotic resistance might have helped the bacteria to survive
and persist in the environment. EHEC outbreaks usually only last around two weeks, but this outbreak has been going on
the bacteria are still infecting people. That source remains a mystery. A case-control study of female patients
but not the bacteria responsible for the ourbreak themselves. Fresh vegetables are still the prime suspect
but Flemming Scheutz, head of THE WHO Collaborative Centre for Reference and Research on Escherichia and Klebsiella in Copenhagen, suggests that the bacteria might not have originated in the food chain at all.
In addition to the antibiotic-resistance genes, the bacteria contain a gene for resistance to the mineral tellurite (tellurium dioxide.
Some strains of bacteria may have evolved resistance to tellurium during its historical medical use, or after its use in the mining and electronics industries increased its presence in the environment.
The ongoing genetic characterization of the strain might also reveal why the bacteria is mostly infecting adults,
an adhesion protein that allows the bacteria to attach to cells in the gut. Eae-negative E coli have been associated specifically with adult infections before
although it is still unclear why this particular protein is more effective in adult guts than in those of children.
Gad Frankel, a microbiologist at Imperial College London, suspects that the genome of this strain will reveal more information about the adherence mechanisms of E coli.
Some pathogenic bacteria don't just stick to cells in our guts, they also have active adherence mechanisms to stick to some vegetables,
The bacterium Agrobacterium tumefaciens which can cause tumours on plants shuttled foreign genes into plant genomes.
Developers then used genetic control elements derived from pathogenic plant viruses such as the cauliflower mosaic virus to switch on the genes.
And Agrobacterium is not essential either; foreign genes can be fired into plant cells on metal particles shot from a'gene gun'.
Now we can foresee this loophole getting wider and wider as companies turn more to plants and away from bacteria and other plant-pest organisms.
Nevertheless, Agrobacterium is still industry's tool of choice for shuttling in foreign genes, says Johan Botterman, head of product research at Bayer Bioscience in Ghent, Belgium.
But Agrobacterium isn't suitable for some new techniques. Many companies are developing'mini-chromosomes'that can function in a plant cell without needing to be integrated into the plant's genome.
unlike the near-random scattering generated by Agrobacterium. In 2009 researchers at Dow Agrosciences in Indianapolis, Indiana,
which has added genes from the Bacillus thuringiensis bacterium, making the plant produce toxins that confer resistance to some insect pests.
Maryland, is the brainchild of Gary Stacey, an expert in host-microbe interactions in plants at the University of Missouri in Columbia.
Friendly bacteria move in mysterious ways: Nature Newsmany yoghurts are loaded with live bacteria, and labelled with claims that consuming these microorganisms can be good for your health.
But a study published today shows that such yoghurts have only subtle effects on the bacteria already in the gut
and do not replace them. Nathan Mcnulty, a microbiologist at Washington University in St louis, Missouri, recruited seven pairs of identical twins,
and asked one in each pair to eat twice-daily servings of a popular yoghurt brand containing five strains of bacteria.
By sequencing BACTERIAL DNA in the twins'stool samples, the team showed that the yoghurt microbes neither took up residence in the volunteers'guts,
nor affected the make-up of the local bacterial communities. Jeffrey Gordon, the microbiologist at Washington University who led the study,
was not surprised. We were only giving several billion bacterial cells in total to the twins,
who harbour tens of trillions of gut microbes in their intestines, he says. Mcnulty also fed the five bacterial strains from the yoghurt to'gnotobiotic'mice animals raised
so that the only microorganisms that their guts contain are 15 species found in humans. As with the twins, the yoghurt bacteria did not change the composition of the rodents'resident communities.
However the activity of genes that allow the native bacteria to break down carbohydrates did increase.
One of the five yoghurt strains Bifidobacterium animalis lactis also showed a similar boost in its ability to metabolize carbohydrates.
The study, which was funded by the US National institutes of health and Danone Research, the research arm of the food company that makes some probiotic yoghurts,
was published in Science Translational Medicine1. Companies that sell foods with added ingredients that are intended to boost health
or prevent illness are under increasing pressure to substantiate the claims about their products. The pressure was increased earlier this year
because there is so much variety in the bacteria in the yoghurts and in the people who consume them,
or sequence their bacterial genes at enough depth. We should reserve the judgement on the effects of probiotics in humans until broader and deeper studies are carried out,
However, he cautions that there are limits to studying mice with human gut bacteria because different species have their own specifically evolved sets.
Gordon now wants to find out exactly how the ingested microbes influence the entrenched ones. These are very dynamic systems with a lot of cross-talk,
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