 |
|
Yale researchers discover Legionnaire microbe's tricks
June 20, 2008Yale University researchers have shed new light how bacteria like the ones that cause Legionnaires' disease and Q-fever raise such havoc in human patients.
In order to survive, the gram-negative bacteria use genes that have evolved in tandem with ones in their hosts to essentially disarm immune system cells trying to kill them, the scientists report Friday in the journal Science.
"Because of their life style, trying to identify how these organisms cause disease has been really difficult,'' said Craig Roy, professor at the Yale School of Medicine in the section of microbial pathogenesis.
Roy and his group described one innovative way the organisms inflict their damage with impunity.
Some gram-negative pathogens such as Legionella pneumophila, and Coxiella burnetii, the cause of Q fever, actually secrete proteins into eukaryotic cells, or cells with a nucleus. But exactly what those proteins did was not known.
Legionnaires' disease is a dangerous form of pneumonia often contracted by inhaling water droplets containing the organism. Q-fever in humans can cause high fevers, chills and can also develop into pneumonia. Both often go undiagnosed.
Previous genome scans of the gram-negative bacteria that cause these diseases had identified a high prevalence of genes called Anks, for ankyrin repeat homology domains. These genes fascinated scientists because they appear very similar to numerous genes in eukaryotic cells that regulate a multitude of processes. These bacteria have "borrowed'' or co-evolved genes from their hosts to survive in the cell. In fact, some species of these bacteria cannot exist outside of a eukaryotic cell.
Roy's lab showed that Ank proteins are secreted into immune system cells called macrophages, and once inside, turn off mechanisms within the cell designed to destroy the bacteria.
Roy believes that more such survival tricks of gram-negative pathogens will be found but adds, "this study at least gives us a foothold" for further study.
Because these bacteria tend to behave like viruses and actually invade cells, they might be susceptible to a vaccine that targets specific elements of the Ank protein and allow macrophages to complete the job, he said.
Yale University
Roy and his group described one innovative way the organisms inflict their damage with impunity.
Some gram-negative pathogens such as Legionella pneumophila, and Coxiella burnetii, the cause of Q fever, actually secrete proteins into eukaryotic cells, or cells with a nucleus. But exactly what those proteins did was not known.
Legionnaires' disease is a dangerous form of pneumonia often contracted by inhaling water droplets containing the organism. Q-fever in humans can cause high fevers, chills and can also develop into pneumonia. Both often go undiagnosed.
Previous genome scans of the gram-negative bacteria that cause these diseases had identified a high prevalence of genes called Anks, for ankyrin repeat homology domains. These genes fascinated scientists because they appear very similar to numerous genes in eukaryotic cells that regulate a multitude of processes. These bacteria have "borrowed'' or co-evolved genes from their hosts to survive in the cell. In fact, some species of these bacteria cannot exist outside of a eukaryotic cell.
Roy's lab showed that Ank proteins are secreted into immune system cells called macrophages, and once inside, turn off mechanisms within the cell designed to destroy the bacteria.
Roy believes that more such survival tricks of gram-negative pathogens will be found but adds, "this study at least gives us a foothold" for further study.
Because these bacteria tend to behave like viruses and actually invade cells, they might be susceptible to a vaccine that targets specific elements of the Ank protein and allow macrophages to complete the job, he said.
Yale University
Bacteria Current Events and Bacteria News RSSFactors from common human bacteria may trigger multiple sclerosis
Current research suggests that a common oral bacterium may exacerbate autoimmune disease. The related report by Nichols et al, "Unique Lipids from a Common Human Bacterium Represent a New Class of TLR2 Ligands Capable of Enhancing Autoimmunity," appears in the December 2009 issue of The American Journal of Pathology.
Exposure to both traffic, indoor pollutants puts some kids at higher risk for asthma later
New research presents strong evidence that the "synergistic" effect of early-life exposure to both outdoor traffic-related pollution and indoor endotoxin causes more harm to developing lungs than one or the other exposure alone.
New study finds MRSA on the rise in hospital outpatients
The community-associated strain of the deadly superbug MRSA-an infection-causing bacteria resistant to most common antibiotics-poses a far greater health threat than previously known and is making its way into hospitals, according to a study in the December issue of Emerging Infectious Diseases.
Researchers establish common seasonal pattern among bacterial communities in Arctic rivers
New research on bacterial communities throughout six large Arctic river ecosystems reveals predictable temporal patterns, suggesting that scientists could use these communities as markers for monitoring climate change in the polar regions.
Biologists discover bacterial defense mechanism against aggressive oxygen
Bacteria possess an ingenious mechanism for preventing oxygen from harming the building blocks of the cell.
Saving the single cysteine: new antioxidant system found
We've all read studies about the health benefits of having a life partner. The same thing is true at the molecular level, where amino acids known as cysteines are much more vulnerable to damage when single than when paired up with other cysteines.
Beyond sunlight: Explorers census 17,650 ocean species between edge of darkness and black abyss
Census of Marine Life scientists have inventoried an astonishing abundance, diversity and distribution of deep sea species that have never known sunlight - creatures that somehow manage a living in a frigid black world down to 5,000 meters (~3 miles) below the ocean waves.
Surface bacteria maintain skin's healthy balance
On the skin's surface, bacteria are abundant, diverse and constant, but inflammation is undesirable. Research at the University of California, San Diego School of Medicine now shows that the normal bacteria living on the skin surface trigger a pathway that prevents excessive inflammation after injury.
On the Trail of a Vaccine for Lyme Disease: Yale Researchers Target Tick Saliva
A protein found in the saliva of ticks helps protect mice from developing Lyme disease, Yale researchers have discovered. The findings, published in the November 19 issue of Cell Host & Microbe, may spur development of a new vaccine against infection from Lyme disease, which is spread through tick bites.
Cigarettes Harbor Many Bacteria Harmful to Human Health
Cigarettes are "widely contaminated" with bacteria, including some known to cause disease in people, concludes a new international study conducted by a University of Maryland environmental health researcher and microbial ecologists at the Ecole Centrale de Lyon in France.
More Bacteria Current Events and Bacteria News Articles
 |
A Field Guide to Bacteria (Comstock Book) by Betsey Dexter Dyer (Author) Pocket-guide to observing bacteria without a laboratory or fancy equipment. Presents all the major taxonomic groups of bacteria in a useable, accessible format for amateur naturalists who may or may not have access to a microscope. Includes ideas for planning field trips to explore bacteria in their natural environments. Illustrated, some color. Softcover, hardcover available. |
 |
Ein-O Science BioSigns Bacteria by Tedco The hands on cell and microbiology models provide magnified and cross section details. The set includes Virus, Bacteria, Plant Cell, White Blood Cell, Red Blood Cell and Animal Cell. Ein-O's I Know Guides and storage box are included. Consider using these models with a display of your own making - featuring the intricacies of cell structure, comparing and contrasting differences, investigating functions & interactions, or describing the efforts of modern medicine... a neat Science Fair Project. Virus - This hands-on interactive model provides magnified and cross-sectioned detailing of a Virus. Animal Cell - This hands-on interactive model provides magnified and cross-sectioned detailing of an Animal Cell. White Blood Cell - This hands-on interactive model provides... |
 |
Bacteria (Discovery Channel School Science) by Lynn Brunelle (Author), Barbara Ravage (Author), Lynn Brunelle (Editor), Barbara Ravage (Editor), Gareth Stevens Publishing (Editor) |
 |
Good Germs, Bad Germs: Health and Survival in a Bacterial World by Jessica Snyder Sachs (Author) Making Peace with Microbes Public sanitation and antibiotic drugs have brought about historic increases in the human life span; they have also unintentionally produced new health crises by disrupting the intimate, age-old balance between humans and the microorganisms that inhabit our bodies and our environment. As a result, antibiotic resistance now ranks among the gravest medical problems of modern times. Good Germs, Bad Germs addresses not only this issue but also what has become known as the “hygiene hypothesis”— an argument that links the over-sanitation of modern life to now-epidemic increases in immune and other disorders. In telling the story of what went terribly wrong in our war on germs, Jessica Snyder Sachs explores our emerging understanding of the symbiotic... |
 |
60 Minutes - Superbug (November 11, 2007) Airdate 11/11/07 MRSA is a superbug, a staff infection that has moved out of hospitals and nursing homes and is now infecting healthy people, sometimes killing them. That's because once the MRSA infection gets into the blood stream, it is largely resistant to antibiotics. For now, the best medicine is prevention. What does this mean? Scrubbing down school desks? Hosing down team locker rooms? Sending infected kids home? Lesley Stahl reports. This product is manufactured on demand using DVD-R recordable media. Amazon.com's standard return policy will apply. |
 |
Molecular Genetics of Bacteria (Snyder, Molecular Genetics of Bacteria) by Larry Snyder (Author), Wendy Champness (Author) This landmark volume provides the single most comprehensive and authoritative textbook on bacterial molecular genetics. Perfect for advanced undergraduate and graduate-level courses, the text presents the latest research on the subject in a clearly written and well-illustrated style. It provides descriptive background information, detailed experimental methods, examples of genetic analyses, and advanced material relevant to current applications of molecular genetics. While providing a deep understanding of bacterial molecular genetics, the material is integrated with biochemical, genomic, and structural information to broaden understanding. The approach centers on the most-studied bacteria, Escherichia coli and Bacillus subtilis. In addition, examples from other bacteria with... |
 |
Magic School Bus World of Germs Science Kit by Young Scientist Club The World of Germs- Magic School Bus Science Kit FUN |
 |
Disposable EARLOOP Face MASK, Filters Bacteria 3 Ply - (Box of 50) by EVERREADY FIRST AID Tie-on surgical face mask with high bacterial filtration efficiency (BFE), low breathing resistance, soft, odorless, non-irritating, comfortable superior fit, fiberglass free. |
 |
Essick Air #1970 Quart Bacteria Treatment by ESSICK AIR PRODUCTS QT, Humidifier Bacteria Treatment, Helps Fight Bacteria & Algae Build Up, Keeps Water Smelling Clean, EPA Registered, For Use In All Evaporative Console & Room Size Humidifiers. |
 |
Enzymatic Therapy Acidophilus Pearls (90 Pearls) by Enzymatic This formula provides a combination of Acidophilus and Bididiobacterium species to support the overall health of the intestinal tract. |
| © 2009 BrightSurf.com |