The role of root infection by insect-carried bacterial pathogens has been underestimated greatly said Evan Johnson a research assistant scientist with UF's Institute of food and agricultural sciences.
and leaves behind bacteria that spread through the tree. Johnson said the bacteria travel quickly to the roots where they replicate damage the root system and spread to the rest of the host tree's canopy.
The disease starves the tree of nutrients leaving fruits that are green and misshapen unsuitable for sale as fresh fruit or juice.
We are still trying to determine how the bacteria are killing the roots Johnson said.
and its symbiotic bacteria work together to make up a single organismal system. The study titled Aphid amino acid transporter regulates glutamine supply to intracellular bacterial symbionts is published in the journal Proceedings of the National Academy of Science (PNAS.
The findings show how a simple mechanism allows an insect the pea aphid to regulate the manufacturing of essential nutrients supplied by its symbiotic bacteria called Buchnera aphidicola.
We've identified the key regulator of this symbiosis said Alex C. C. Wilson associate professor of Biology in the College of Arts and Sciences and corresponding author of the study.
but the rest it must get from beneficial bacteria that live inside aphid cells. In turn the symbiotic bacteria can't produce amino acids that the aphid can make so the partners exchange insect-produced amino acids for symbiont-produced amino acids.
That conversion of going from a diet with an inappropriate nutritional profile to an appropriate profile occurs in collaboration between the bacteria
and the host Wilson said. The question is whether the production of nutrients changes with supply
Glutamine is ferried across a membrane that surrounds the cells where the bacteria lives by an amino acid transporter named Apglnt1.
Since glutamine is a precursor for amino acids the bacteria's synthesis of arginine is reduced in turn.
Since Apglnt1 localizes to the membrane of aphid cells where the bacteria resides and because of other features peculiar to aphid metabolism transporter Apglnt1 not only regulates arginine biosynthesis
Wilson's lab may find the answer by looking at other sap-feeding insects with intracellular bacteria based on an understanding that emerged from another study from her lab. The study titled Dynamic recruitment of amino acid transporters to the insect
and often infected by fleas with plague bacteria Knutie says. Permethrin has been sprayed in burrows but that is labor-intensive so it might be used on vegetation the animals drag into their burrows.
tomato eaters winscientists from the U s. Food and Drug Administration (FDA) have identified a benign bacterium that shows promise in blocking Salmonella from colonizing raw tomatoes.
When applied to Salmonella-contaminated tomato plants in a field study the bacterium known as Paenibacillus alvei significantly reduced the concentration of the pathogen compared to controls.
Many innocuous bacterial species thrive within the tomato-growing environment. We hypothesized that such an organism could be found that possessed the ability to outcompete
After screening many hundreds of potential biocontrol strains of bacteria that were isolated from farms and natural environments in the Mid-atlantic region we found about 10 isolates of bacteria representing very different genera
and species that could curb the growth and/or destroy Salmonella in our test assays.
This bacterium also has known no history of human pathology making it a great candidate as a biological control agent says Zheng.
The results demonstrate that the bacterial pathogens were inhibited significantly by the use of the antimicrobial films said Catherine Cutter professor of food science.
In the study which was published online in the April issue of the Journal of Food Science researchers determined survivability of bacterial pathogens after treatment with 2 percent oregano essential oil 2 percent rosemary essential oil
and the researchers determined the antimicrobial activity of these films against bacterial pathogens inoculated onto petri dishes.
and poultry products with bacterial pathogens treated them with the pullulan films containing the essential oils
and then evaluated for bacterial growth following refrigerated storage for up to three weeks. The results from this study demonstrated that edible films made from pullulan
because the bacteria-killing action is longer lasting. Liquid applications run off the surface are absorbed not
The pullulan films adhere to the meat allowing the incorporated antimicrobials to slowly dissolve providing immediate and sustained kill of bacteria.
and keep bacteria in meat at bay further research will be aimed at creating what Cutter referred to as active packaging--polyethylene film with antimicrobial properties.
Specifically the so-called MR (mannose receptor) could be a safe door of entry for certain bacteria protozoa parasites and viruses like SRLVS into the target cell
According to a recent study by Kansas State university published in the Applied and Environmental Microbiology journal insects carry antibiotic-resistant bacteria from one point to another including from food animal farms and wastewater treatment
The researchers then genetically analyzed the bacteria in the digestive tract of the insects and compared them to the bacteria present in the animal feces and wastewater.
We found these insects carry the same bacteria found in the animal manure Zurek said.
Then we started sampling insects found in surrounding urban areas including fast food restaurants and again we found house flies with multi-drug resistant bacteria.
The house flies collected from the wastewater treatment plants likewise carried the same bacteria found in the waste itself he said.
House flies collected several miles from the wastewater treatment plants in surrounding urban areas had a lower prevalence of the antibiotic-resistant bacteria than those examined from the facilities themselves
but the bacteria still existed in those urban house flies. The study led the researchers to conclude that insects primarily house flies can pick up antibiotic-resistant bacteria
and disseminate them to surrounding areas. How serious that link is still needs to be investigated
but the potential is clearly there Zurek said. Cockroaches and house flies are highly mobile
They have great potential to move multi-drug resistant bacteria to urban areas. In addition Zurek's team showed that bacteria in the house fly digestive tract can exchange antibiotic resistance by horizontal gene transfer.
The resistant strains multiply in the fly and can be left behind on food by fly regurgitation or spitting and defecation.
Unfortunately because of the intensive use of antibiotics in human medicine we pose high pressure on bacteria
The bacteria that caused the infections are multi-drug resistant. According to a 2013 report by the Centers for Disease Control and Prevention (http://www. cdc. gov/drugresistance/threat-report-2013) at least 2 million people become infected with antibiotic-resistant bacteria
and at least 23000 people die each year as a direct result of these infections in the United states. Currently two places where antibiotics are used most widely are hospitals
At the same time if you use low doses of antibiotics extensively that poses selective pressure on bacteria in the digestive tract of these animals and results in antibiotic resistance.
and crows carry multi-drug antibiotic-resistant bacteria. Wild birds can pick up the antibiotic resistant bacteria from fields where animal manure was used as a fertilizer he said.
We still don't know how significant these birds are as carriers. We just know there are multiple venues where wildlife can acquire resistant strains and move them around in the environment.
Lowering the use of antibiotics in animal industry will be another step to lower prevalence of antibiotic resistant bacteria in the environment
They can carry antibiotic resistant bacteria so they should be taken seriously as a vector. Story Source:
#Bacteria combat dangerous gas leaksbacteria could mop up naturally-occurring and human-made leaks of natural gases before they are released into the atmosphere and cause global warming according to new research from the University of East Anglia.
Findings published today in the journal Nature shows how a single bacterial strain (Methylocella silvestris) found in soil
and other gaseous alkanes such as propane was carried out by different groups of bacteria. This new finding is important
because it means that one type of bacteria can mop up the components of natural gas very efficiently
Researchers studied the bacterium Methylocella which is normally found in peat tundra and forest soils in Northern europe.
This type of bacterium has also been found among the microbial community following the Deepwater horizon oil spill in 2010.
#How a plant beckons bacteria that will do it harma common plant puts out a welcome mat to bacteria seeking to invade
This signaling system triggers a structure in bacteria that actually looks a lot like a syringe
It's exciting to learn that metabolites excreted by the host can play a role in triggering this system in bacteria said Thomas Metz an author of the paper and a chemist at the Department of energy's Pacific Northwest National Laboratory.
The work focused on bacteria known as Pseudomonas syringae pv. tomato DC3000 which can ruin tomatoes as well as Arabidopsis.
The bacteria employ a molecular system known as the Type 3 Secretion System or T3ss to infect plants.
The researchers discovered a group of five acids that collectively had the biggest effect on turning on the bacteria's T3ss:
Since the resistant plants don't have high levels of these acids it stops the bacteria from unfurling the syringe in the presence of the plant.
or molecules that the plant uses to recognize the bacteria as a strategy for evading detection said Peck associate professor of biochemistry at the University of Missouri
While Peck's study focused on bacteria known mostly for damaging tomatoes the findings also could have implications for people.
The work opens the door to new ways to rendering harmful bacteria harmless by modifying plants
Rather than trying to kill the bacteria eliminating the recognition signals in the plant makes the bacteria fairly innocuous giving the natural immune system more time to defend itself.
which is used commonly as a farm soil fertilizer contains a surprising number of newly identified antibiotic resistance genes from the cows'gut bacteria.
The findings reported in mbioâ the online open-access journal of the American Society for Microbiology hints that cow manure is a potential source of new types of antibiotic resistance genes that transfer to bacteria in the soils
when found in harmless bacteria. The real worry is when these genes appear in the types of pathogenic bacteria that cause food-borne illnesses
or hospital infections Since there is a connection between AR genes found in environmental bacteria and bacteria in hospitals we wanted to know what kind of bacteria are released into the environment via this route of manure fertilization says Fabienne Wichmann lead study author and former postdoctoral researcher at Yale university in New haven Connecticut.
Farmers use raw or composted cow manure on some vegetable crops which could lead to a scenario where residual manure bacteria might cling to produce
and they or their genes might move to the human ecosystem. Is this a route for movement of these genes from the barn to the table?
asks Jo Handelsman senior study author and microbiologist at Yale. The first step toward an answer was surveying
The genes made a laboratory strain of Escherichia coli bacteria resistant to one of four types of antibiotics--beta-lactams (like penicillin) aminoglycosides (like kanamycin) tetracycline or chloramphenicol.
That might signal good news that AR genes from cow gut bacteria are not currently causing problems for human patients.
AR genes can enter the human ecosystem by two routes--either the bacteria that contain them colonize humans
or the genes are transferred through a process called horizontal gene transfer to other bacteria that colonize humans.
Research has shown already that bacteria are transferred from farm animals to their human caretakers. Gene transfer enables genes to jump between microorganisms that are related not
and it occurs in most environments that host bacteria. Some manure bacteria might be pathogenic to humans
so if they acquire antibiotic resistance they could pose a problem. Alternatively benign bacteria in manure might transfer resistance genes to pathogens at any point along the path--in manure soil food or humans.
We're hoping this study will open up a larger field of surveillance to start looking at new types of resistance before they show up in the clinic says Handelsman.
when bacteria take advantage of the open vagina and cervix to settle in the uterus. Infected cows suffer fever pain inflammation lack of appetite depression and reduced reproductive abilities.
#Pathogenic E coli binds to fresh vegetablesfood-poisoning outbreaks linked to disease-causing strains of the bacterium Escherichia coli are associated normally with tainted meat products.
H7 uses whip-link structures on its surface known as flagella--typically used for bacterial motility--to penetrate the plant cell walls.
E coli bacteria lacking flagella were unable to bind to the plant cells. Once attached the E coli are able to grow on and colonise the surface of the plant.
although the researchers showed that a small number of bacteria are able to invade inside the plant where they become protected from washing.
This work shows the fine detail of how the bacteria bind to plants. We think this mechanism is common to many food-borne bacteria
and shows that they can exploit common factors found in both plants and animals to help them grow.
H7 bacteria use the same method of colonising the surface of plants as they do when colonising the intestines of animals.
The work shows that these bacteria are transported not simply through the food chain in an inert manner
By understanding the mechanisms of how the bacteria interact with plants the researchers are hoping to find targeted ways to stop the binding reducing the risk of food contamination.
For more than a century milk has been heated to kill any bacteria or pathogens that can affect consumer health and shorten the shelf life of the product.
As the colony expands the layers form a biofilm that feeds and protects the organisms.
Many of these biofilm-embedded organisms cannot be inactivated through conventional cleaning methods. Milk products containing high microbe counts have flavor texture
and his team of eight graduate and 10 undergraduate researchers worked on projects related to thermoduric bacteria and biofilms.
The team then isolates the heat resistant bacteria. South dakota's dairy industry produces 1. 8 billion pounds of milk and 232 million pounds of cheese producing a total economic impact of $1. 28 billion a year.
Knocking out coloniesin addition the team has targeted also microbial biofilms which form on joints plate heat exchangers and filtration membranes within the milk processing equipment.
and cultured to develop single and multi-species biofilms. Under lab conditions a biofilm can takes anywhere from 12 to 48 hours to form he comments.
This process helps the researchers determine under what conditions the biofilms form and ultimately how we can change our cleaning system to remove them more efficiently
and effectively Anand explains. The biofilm embedded microbes are studied not only in a static system but also in bioreactors
which simulate the continuous flow of milk or whey. This is closer to the real system Anand says though the bioreactors are pressurized not like the automatic processing system.
and form biofilms. Through this multipronged approach at lowering thermoduric microbe levels the SDSU researcher hopes to improve the quality safety and shelf life of dairy products.
and cutting boards remain a source of transmission for multi-drug resistant bacteria such as E coli that produce extended-spectrum beta-lactamases (ESBLS).
The spread of multi-drug resistant bacteria has been associated with the hospital setting but these findings suggest that transmission of drug-resistant E coli occurs both in the hospital
or fish were contaminated with any ESBL-producing bacteria. They also found that the meat's country of origin did not play a factor in the presence of bacteria on any of the surfaces.
Story Source: The above story is provided based on materials by Society for Healthcare Epidemiology of America.
and limits photosynthesis. Particular types of bacteria consume methane creating food for grazing insects and consequently the rest of the food web including trout.
biotic generally caused by infectious organisms like bacteria; and abiotic caused by environmental agents like nutrient deficiency flood and salinity.
The scientists looked at the genes'response to five abiotic stresses--drought heavy metal contamination salt cold and nutrient deprivation--and five biotic stresses--bacteria fungus insect predation weed
A bacterium called Candidatus Liberibacter asiaticus (CLAS) vectored by the Asian citrus psyllid is presumed the causal agent of the disease.
and because those maladies are linked often to bacteria he said. The UF researchers did their experiments in labs
because cattle uteri have a neutral ph. The study's findings suggest chitosan microparticles kill bacteria in the uteri he said.
Once bacteria become resistant whether on farms hospitals or in the environment they can infect humans through water food
and animals kill good and bad bacteria. Scientists can use the UF study's findings to begin to develop better drugs that target bad pathogens
but leave beneficial bacteria Jeong said. E coli are everywhere including the human gut but can contaminate beef unpasteurized milk soft cheeses made from raw milk
Listeria is a rod-shaped bacterium highly prevalent in the environment and generally not a threat to human health.
two distinct bacterial strains which had evolved not recently from a common ancestor and therefore entered the food chain independently.
and that possible food for the bacteria be limited. Any products listeria is found in must be recalled immediately.
The team concluded that the bacteria and fungi that decompose plant matter in healthy ecosystems are hindered by radioactive contamination.
Researchers have reported just that certain bacteria in the stomach gobble the chocolate and ferment it into anti-inflammatory compounds that are good for the heart.
The good microbes such as Bifidobacterium and lactic acid bacteria feast on chocolate she said. When you eat dark chocolate they grow
The other bacteria in the gut are associated with inflammation and can cause gas bloating diarrhea and constipation.
He said that this study is the first to look at the effects of dark chocolate on the various types of bacteria in the stomach.
They then subjected the nondigestible materials to anaerobic fermentation using human fecal bacteria according to Finley.
but that good bacteria like to eat. This food for your gut's helpful inhabitants also comes in dietary supplements.
and tested the tags using E coli (food-spoiling bacteria that cause gastrointestinal problems) in milk as a reference model.
#Honey offers new approach to fighting antibiotic resistancehoney that delectable condiment for breads and fruits could be one sweet solution to the serious ever-growing problem of bacterial resistance to antibiotics
The unique property of honey lies in its ability to fight infection on multiple levels making it more difficult for bacteria to develop resistance said study leader Susan M. Meschwitz Ph d. That is it uses a combination of weapons including hydrogen peroxide
and polyphenols--all of which actively kill bacterial cells she explained. The osmotic effect which is the result of the high sugar concentration in honey draws water from the bacterial cells dehydrating
and killing them. In addition several studies have shown that honey inhibits the formation of biofilms or communities of slimy disease-causing bacteria she said.
Honey may also disrupt quorum sensing which weakens bacterial virulence rendering the bacteria more susceptible to conventional antibiotics Meschwitz said.
Quorum sensing is the way bacteria communicate with one another and may be involved in the formation of biofilms.
In certain bacteria this communication system also controls the release of toxins which affects the bacteria's pathogenicity or their ability to cause disease.
Meschwitz who is with Salve Regina University in Newport R i. said another advantage of honey is that unlike conventional antibiotics it doesn't target the essential growth processes of bacteria.
The problem with this type of targeting which is the basis of conventional antibiotics is that it results in the bacteria building up resistance to the drugs.
Honey is effective because it is filled with healthful polyphenols or antioxidants she said. These include the phenolic acids caffeic acid p-coumaric acid and ellagic acid as well as many flavonoids.
Several studies have demonstrated a correlation between the non-peroxide antimicrobial and antioxidant activities of honey and the presence of honey phenolics she added.
A large number of laboratory and limited clinical studies have confirmed the broad-spectrum antibacterial antifungal and antiviral properties of honey according to Meschwitz.
She said that her team also is finding that honey has antioxidant properties and is an effective antibacterial.
Without these trash bins the Escherichia coli bacteria they serve would die. And thanks to Rice the how is becoming clearer.
He said understanding essential motor proteins in bacteria will be important as researchers begin to apply DCA to advance human health.
Another possibility is that commensal bacteria in the gut could offer humans a helping hand in digesting milk.
The team is now assaying Africans'gut bacteria to see if that might be the case.
The shrub bacteria are more like what they found in open prairie than in the forest.
because the product isn't pasteurized it contains good bacteria that can increase lactose absorption.
me because regardless of the bacteria raw milk and pasteurized milk have the same amount of lactose in them Gardner said.
whether their digestive systems adapted to the additional bacteria in raw milk. We brought in focus groups of lactose-intolerant people to get feedback before we started the study
and balances between beneficial and potentially harmful bacteria which characterizes a healthy gut microbiota is disturbed in IBS patients.
Probably the best example of this interaction is the discovery that IBS symptoms develop in up to 10 percent of previously healthy subjects after a single episode of gastroenteritis caused by an infection through bacterial pathogens like Salmonella Shighella or Campylobacter
and treatment we have to identify more of the various functions of the intestinal bacteria.
With regard to clinical applications bacterial functions are even more important than their types. Story Source: The above story is provided based on materials by American Gastroenterological Association.
#Maize and bacteria: A one-two punch knocks copper out of stamp sandscientists have known for years that together bacteria
and plants can remediate contaminated sites. Ramakrishna Wusirika of Michigan Technological University has determined that how you add bacteria to the mix can make a big difference.
He has also shed light on the biochemical pathways that allow plants and bacteria to clean up some of the worst soils on the planet
while increasing their fertility. Wusirika an associate professor of biological sciences first collected stamp sands near the village of Gay in Michigan's Upper Peninsula.
Then Wusirika and his team planted maize in the stamp sand incorporating bacteria in four different ways:
2. coating seed with bacteria and planting it; 3. germinating seeds and planting them in soil to
which bacteria were added; and4. the conventional method immersing the roots of maize seedlings in bacteria
and planting them in stamp sand. After 45 days the team uprooted the plants and measured their dry weight.
All maize grown with bacteria was significantly more vigorous--from two to five times larger--than the maize grown in stamp sand alone.
The usual technique--applying bacteria to seedlings'roots before transplanting--works fine in the lab
But the mere fact that all the plants grown with bacteria did so well also piqued his curiosity.
When we saw this we wondered what the bacteria were doing to the soil Wusirika said.
The bacteria are also changing copper into a form that the plants can take up. With bacteria the exchangeable copper is increased three times he said.
There's still a lot of copper that's not available but it is moving in the right direction.
By analyzing metabolic compounds the team was able to show that the bacteria enhance photosynthesis
Bacteria also appear to affect the amount phenolics produced by the maize. Phenolics are antioxidants similar to those in grapes and red wine.
Compared to plants grown in normal soil without bacteria plants grown in stamp sand alone showed a fivefold increase in phenolics.
However phenolics in plants grown in stamp sand with bacteria showed a lesser increase. Growing in stamp sand is very stressful for plants
Adding the metal-resistant bacteria enables the plants to cope with stress better resulting in reduced levels of phenolics.
but wastewater carries microorganisms such as viruses bacteria and protozoa that can contaminate food and cause disease.
and regulations for the reuse of wastewater they present only threshold concentrations for bacteria such as E coli not viruses.
#Predators delay pest resistance to Bt cropscrops genetically modified with the bacterium Bt (Bacillus thuringiensis) produce proteins that kill pest insects.
Bt is a soil bacterium that produces proteins that are toxic to some species of caterpillars
and cotton plants genetically engineered to produce proteins from the bacterium Bacillus thuringiensis (Bt). These proteins kill some key pests
Consumer concerns about bacterial resistance to antibiotics have prompted the swine industry to seek additional methods to protect the health of pigs including special feed additives.
E coli a bacterial illness of the gut is marked by diarrhea decrease in appetite decrease in body weight and in some cases a higher mortality rate.
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