The Japanese laboratory that retracted a paper reporting a potentially major breakthrough in stem cell research said Wednesday its researchers have not managed to replicate the results. Scientists at the government-affiliated RIKEN Center for Developmental Biology said they are still trying to match results reported in two papers published by Nature in January and then retracted in July.
For the past 10 years, scientists have been fascinated by a type of “electric bacteria” that shoots out long tendrils like electric wires, using them to power themselves and transfer electricity to a variety of solid surfaces. A team led by scientists has now turned the study of these bacterial nanowires on its head, discovering that the key features in question are not pili as previously believed.
Rice Univ. scientists have won a race to find the crystal structure of the first virus known to infect the most abundant animal on Earth. The Rice laboratories of structural biologist Yizhi Jane Tao and geneticist Weiwei Zhong, with help from researchers at Baylor College of Medicine and Washington Univ., analyzed the Orsay virus that naturally infects a certain type of nematode, the worms that make up 80% of the living animal population.
Imitation, they say, is the sincerest form of flattery, but mimicking the intricate networks and dynamic interactions that are inherent to living cells is difficult to achieve outside the cell. Now, as published in Science, Weizmann Institute scientists have created an artificial, network-like cell system that is capable of reproducing the dynamic behavior of protein synthesis.
Recent research has made a significant contribution to the understanding of a new field of DNA research that is based on a repetitive piece of DNA in the bacterial genome called a CRISPR. The study provides the first detailed blueprint for this multi-subunit “molecular machinery” that bacteria use to detect and destroy invading viruses.
A fundamental chemical pathway that all plants use to create an essential amino acid needed by all animals to make proteins has now been traced to two groups of ancient bacteria. The pathway is also known for making hundreds of chemicals, including a compound that makes wood strong and the pigments that make red wine red.
According to recent research that marks the first time investigators have taken a microbial census of a sake brewery, the microbial populations found on surfaces in the facility resemble those found in the product, creating the final flavor. This means a sake brewery has its own microbial terroir.
The drought that has the entire country in its grip is affecting more than the color of people’s lawns. It may also be responsible for the proliferation of a heat-loving amoeba commonly found in warm freshwater bodies, such as lakes, rivers and hot springs, which the drought has made warmer than usual this year.
When it comes to swimming, the bodies of some bacteria are more than just dead weight, according to new research from Brown Univ. Many bacteria swim using flagella, corkscrew-like appendages that push or pull bacterial cells like tiny propellers. It's long been assumed that the flagella do all the work during swimming, while the rest of the cell body is just along for the ride.
Researchers in Kentucky have developed a technology that uses male mosquitoes to effectively sterilize females through a naturally occurring bacterium. Called MosquitoMate, the new technology has been issued an experimental use permit for open field releases targeting the invasive Asian tiger mosquito, which is a vector for newly introduced pathogens like the Chikungunya virus.
We are all creatures of habit, and a new study finds ocean bacteria are no exception. In a paper published in Science, researchers report that microbes in the open ocean follow predictable patterns of biological activity, such as eating, breathing and growing. Certain species are early risers, exhibiting genetic signs of respiration, metabolism and protein synthesis in the morning hours, while others rouse to action later in the day.
Researchers from North Carolina State Univ. and the Univ. of Minnesota have found, for the first time, that genetically identical strains of bacteria can respond very differently to the presence of sugars and other organic molecules in the environment, with some individual bacteria devouring the sugars and others ignoring it.
Using the quantitative approach of physicists, biologists in Israel have developed experimental tools to measure precisely the bacterial response to antibiotics. Their mathematical model of the process has led them to hypothesize that a daily three-hour dose would enable the bacteria to predict delivery of the drug, and go dormant for that period in order to survive.
Genomic sequencing is supposed to reveal the entire genetic makeup of an organism. The technology can be used to analyze a disease-causing bacterium to determine how much harm it is capable of causing. But new research at Rockefeller Univ. suggests that current sequencing protocols overlook crucial bits of information: isolated pieces of DNA floating outside the bacterial chromosome, the core of a cell’s genetic material.
Trillions of bacteria live in and on the human body; a few species can make us sick, but many others keep us healthy by boosting digestion and preventing inflammation. Although there's plenty of evidence that these microbes play a collective role in human health, we still know very little about most of the individual bacterial species that make up these communities.
Researchers at The Johns Hopkins Univ. report they have deciphered the inner workings of a protein called YiiP that prevents the lethal buildup of zinc inside bacteria. They say understanding YiiP's movements will help in the design of drugs aimed at modifying the behavior of ZnT proteins, eight human proteins that are similar to YiiP, which play important roles in hormone secretion and in signaling between neurons.
Researchers at the Univ. of Michigan have obtained the first 3-D snapshots of the "assembly line" within microorganisms that naturally produces antibiotics and other drugs. Understanding the complete structure and movement within the molecular factory gives investigators a solid blueprint for redesigning the microbial assembly line to produce novel drugs of high medicinal value.
Sweaty hands can reduce the effectiveness of bacteria-fighting brass objects in hospitals and schools after just an hour of coming into contact with them, according to scientists at the Univ. of Leicester. While copper found in everyday brass items has an antimicrobial effect on bacteria the team has discovered that peoples’ sweat can produce sufficient corrosion to adversely affect its use to kill a range of microorganisms.
A biological detection technology developed by Lawrence Livermore National Laboratory scientists can detect bacterial pathogens in the wounds of U.S. soldiers that have previously been missed by other technologies. This advance may, in time, allow an improvement in how soldiers' wounds are treated.
Nanopores may one day lead a revolution in DNA sequencing. By sliding DNA molecules one at a time through tiny holes in a thin membrane, it may be possible to decode long stretches of DNA at lightning speeds. Scientists, however, haven’t quite figured out the physics of how polymer strands like DNA interact with nanopores.
An international team of scientists, led by researchers at the Univ. of California, San Diego School of Medicine, have identified the genes encoding a molecule that famously defines Group A Streptococcus (strep), a pathogenic bacterial species responsible for more than 700 million infections worldwide each year.
Much as human DNA can be used as evidence in criminal trials, genetic information about microorganisms can be analyzed to identify pathogens or other biological agents in the event of a suspicious disease outbreak. The tools and methods used to investigate such outbreaks belong to the new field of microbial forensics, but the field faces substantial scientific and technical challenges, says a new report from the National Research Council.
Staph infections that become resistant to multiple antibiotics don't happen because the bacteria themselves adapt to the drugs, but because of a kind of genetic parasite they carry called a plasmid that helps its host survive the antibiotics. Plasmids are rings of bare DNA containing a handful of genes that are essentially freeloaders, borrowing most of what they need to live from their bacterial host.
Hospital germs can be fatal, since they are resistant to antibiotics. As a result, alternative methods of defense against bacteria are in demand. Fortunately, a German-French research team has been able to develop bone implants that keep the germs at bay. The solutions depends on a breakthrough that allows scientists to imbue apatite crystals with calcium phosphate.
Bacteria use threadlike appendages, called pili, to creep along a surface, and some disease-causing microbes extend pili in all directions to move. But until now researchers have been unable to explain why bacteria like these are able to travel in a straight line consistently. A new model developed to describe this movement shows that bacteria do not act as randomly as they appear to when moving.