Certain bacteria, including Staphylococcus aureus, have the ability to deploy tiny darts. This biological weapon kills the host cell by piercing the membrane. Researchers have unlocked, piece by piece, this intriguing little machine and found an assembly of proteins that, in unfolding at the right time, takes the form of a spur.
A study at the Univ. of Utah finds that more than 60% of antibiotic prescriptions are for types that kill multiple kinds of bacteria. Unfortunately, in more than 25% of cases such prescriptions are useless because the infection stems from a virus, which cannot be treated with antibiotics. This overuse of antibiotics has a number of downsides.
The bacterium Yersinia can cause a variety of symptoms, including abdominal pain, fever and diarrhea. The bacterium’s pathogenic potential is based on a syringe-like injection apparatus called the injectisome. For the first time, an international team of researchers including scientists at the Helmholtz Centre for Infection Research Germany, has unraveled this molecular syringe’s spatial conformation.
All plants need nitrogen to convert into ammonia, but only a small number of plants can fix nitrogen from the atmosphere. The rest are helped by synthetic fertilizers, which have been blamed for nitrogen pollution. A scientist in the U.K., Edward Cocking, has found a specific strain of nitrogen-fixing bacteria in sugar cane which he discovered could intracellularly colonize all major crop plants. The technology is being commercialized.
The use of enzymes from thermophiles—microbes that thrive at extremely high temperatures and alkaline conditions—holds promise for extracting fermentable sugars from lignocellulosic biomass. Finding the most effective of these microbial enzymes has been a challenge, but Joint BioEnergy Institute scientists have recently made progress in this area by adapting a combination of metagenomic and metaproteomic technologies.
The discovery of a gene's function in E. coli and other bacteria might lead to a probiotic to prevent the most common type of kidney stone, according to a Purdue Univ. study. Human cells can't metabolize oxalate, an acidic chemical found in nearly all plants we eat, so any oxalate we absorb from food must be excreted from the body. Calcium-oxalate urinary stones can form when oxalate reaches a high concentration in the kidneys.
Could there come a time in which the carbon dioxide emitted from coal-burning power plants is harvested and used to produce clean, green and renewable liquid transportation fuels? A pathway to that possibility has been opened by a team of researchers with the Joint BioEnergy Institute who have engineered a microbe now being used to produce biodegradable plastic into a strain that can produce a high-performance advanced biofuel.
Purple bacteria contain pigments that allow them to use sunlight as their source of energy. Small as they are, these microbes can teach us a lot about life on Earth, because they have been around longer than most other organisms on the planet. A Univ. of Miami physicist recently found that these organisms can also survive in the presence of extreme alien light.
Using several imaging techniques, Lawrence Berkeley National Laboratory scientists found that a common soil bacterium stays connected by a network of chain-like membranes. They believe the bacterium uses its network to coordinate social activities—such as evading bacterial enemies and snaring prey—without revealing its location.
Microbiologists in France are reinvigorating a way of battling C. difficile infections that they hope will help overcome the growing problem of antibiotic resistant superbugs in hospitals. Using a model human colon, the researchers showed that the administration of a specific bacteriophage significantly reduced toxins and the number of C. difficile cells produced without significantly affecting the other members of the gut microbiota.
The interior of a living cell is a crowded place, with proteins and other macromolecules packed tightly together. A team of scientists at Carnegie Mellon Univ. has approximated this molecular crowding in an artificial cellular system and found that tight quarters help the process of gene expression, especially when other conditions are less than ideal.
Scientists at the Univ. of East Anglia are developing a new class of anti-cancer drugs that are not only powerful but also circumvent a primary cause of resistance to chemotherapy. The work is inspired by nature’s fungus farmer, the leaf cutter ant.
On Monday, the National Academy of Sciences announced a three-year grant to chemist Vincent Rotello at the University of Massachusetts Amherst to develop, test and deploy new, sensitive, reliable and affordable inkjet-printed, nanoparticle-based test strips for detecting disease-causing bacteria in drinking water.
Biomaterials are susceptible to microbial colonization, which is why silver is often added to reduce the adhesion rate of bacteria. However, a recent study by researchers in Portugal suggests that—in one material—increasing levels of silver may indirectly promote bacterial adhesion instead of decrease it.
Research at the University of Massachusetts Amherst has revealed how protein degradation is critical to cell cycle progression and bacterial development. The team used a combination of biochemistry and mass spectrometry to “trap” scores of new candidate substrates of the protease ClpXP. These substrates cover all aspects of bacterial growth and development.
By rerouting the metabolic pathway that makes fatty acids in E. coli bacteria, researchers at Harvard University have devised a new way to produce a gasoline-like biofuel. According to the scientists, who are tweaking metabolic pathways in bacteria, new lines of engineered bacteria can tailor-make key precursors of high-octane biofuels that could one day replace gasoline.
Scientists at the University of Texas at San Antonio and the U.S. Army Institute of Surgical Research have developed a microarray platform for culturing fungal biofilms that holds 1,200 individual cultures of fungi or bacteria. The nano-scale platform technology could one day be used for rapid drug discovery for treatment of any number of fungal or bacterial infections, or even as a rapid clinical test to identify antibiotic drugs.
Bacterial DNA may integrate into the human genome more readily in tumors than in normal human tissue, scientists have found. The researchers analyzed genomic sequencing data available from the Human Genome Project, the 1,000 Genomes Project and The Cancer Genome Atlas. They considered the phenomenon of lateral gene transfer, the transmission of genetic material between organisms in a manner other than traditional reproduction.
A Cornell Univ. study offers further proof that the divergence of humans from chimpanzees some 4 to 6 million years ago was profoundly influenced by mutations to DNA sequences that play roles in turning genes on and off. The study provides evidence for a 40-year-old hypothesis that regulation of genes must play an important role in evolution since there is little difference between humans and chimps in the proteins produced by genes.
Bacteria in the gut that are under attack by antibiotics have allies no one had anticipated, a team of Harvard Univ. Wyss Institute scientists has found. Gut viruses that usually commandeer the bacteria, it turns out, enable them to survive the antibiotic onslaught, most likely by handing them genes that help them withstand the drug.
For the first time, researchers have found a particular kind of molecular switch in the food-poisoning bacteria Salmonella Typhimurium under infection-like conditions. This switch, using a process called S-thiolation, appears to be used by the bacteria to respond to changes in the environment during infection and might protect it from harm, researchers report.
A team of researchers has captured images of green alga consuming bacteria, offering a glimpse at how early organisms dating back more than 1 billion years may have acquired free-living photosynthetic cells. This acquisition is thought to have been a critical first step in the evolution of photosynthetic algae and land plants.
The temperature in the permafrost on Ellesmere Island in the Canadian high Arctic is nearly as cold as that of the surface of Mars. So the recent discovery by a McGill University led team of scientists of a bacterium that is able to thrive at -15 C, the coldest temperature ever reported for bacterial growth, is exciting. The bacterium offers clues about some of the necessary preconditions for microbial life on Mars.
Bacteria on a surface wander around and often organize into highly resilient communities known as biofilms. It turns out that they organize in a rich-get-richer pattern similar to the distribution of wealth in the U.S. economy, according to a new study.
Researchers have cautioned that more work is needed to understand how microorganisms respond to the disinfecting properties of silver nanoparticles, increasingly used in consumer goods and for medical and environmental applications. Although nanosilver has effective antimicrobial properties against certain pathogens, overexposure to silver nanoparticles can cause other potentially harmful organisms to rapidly adapt and flourish.