COLUMBUS, Ohio — According to a new study, smoking causes the body to turn against its own helpful bacteria, leaving smokers more vulnerable to disease.
Despite the daily disturbance of brushing and flossing, the mouth of a healthy person contains a stable ecosystem of healthy bacteria. New research shows that the mouth of a smoker is a much more chaotic, diverse ecosystem—and is much more susceptible to invasion by harmful bacteria. (more…)
*Study implicates “arms race” between genes and germs*
Biologists have found new evidence of why mice, people and other vertebrate animals carry thousands of varieties of genes to make immune-system proteins named MHCs–even though some of those genes make vertebrate animals susceptible to infections and to autoimmune diseases.
“Major histocompatibility complex” (MHC) proteins are found on the surfaces of most cells in vertebrate animals. They distinguish proteins like themselves from foreign proteins, and trigger an immune response against these foreign invaders. (more…)
Humans pump thousands of tons of vapor from the metallic element mercury into the atmosphere each year, and it can remain suspended for long periods before being changed into a form that is easily removed from the atmosphere.
New research shows that the upper troposphere and lower stratosphere work to transform elemental mercury into oxidized mercury, which can easily be deposited into aquatic ecosystems and ultimately enter the food chain. (more…)
*For ancient plants, two genes were definitely better than one*
In the wake of the disaster that killed the dinosaurs, the ancestors of today’s crop plants reinvented themselves.
They doubled their genomes, and in that single act set the stage for feeding the world 60 million years later.
In a study published in the Nov. 16 issue of the journal Nature, researchers from the University of Minnesota and other institutions recount how sequencing the genome of a model, alfalfa-like legume revealed the monumental benefits that flowed when the ancestor of legumes acquired an extra copy of every gene. (more…)
A new mouthwash developed by a microbiologist at the UCLA School of Dentistry is highly successful in targeting the harmful Streptococcus mutans bacteria that is the principal cause tooth decay and cavities.
In a recent clinical study, 12 subjects who rinsed just one time with the experimental mouthwash experienced a nearly complete elimination of the S. mutans bacteria over the entire four-day testing period. The findings from the small-scale study are published in the current edition of the international dental journal Caries Research. (more…)
Critical genetic secrets of a bacterium that holds potential for removing toxic and radioactive waste from the environment have been revealed in a study by researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab). The researchers have provided the first ever map of the genes that determine how these bacteria interact with their surrounding environment.
“Knowing how bacteria respond to environmental changes is crucial to our understanding of how their physiology tracks with consequences that are both good, such as bioremediation, and bad, such as biofouling,” says Aindrila Mukhopadhyay, a chemist with Berkeley Lab’s Physical Biosciences Division, who led this research. “We have reported the first systematic mapping of the genes in a sulfate-reducing bacterium – Desulfovibrio vulgaris – that regulate the mechanisms by which the bacteria perceive and respond to environmental signals.” (more…)
Woods Hole Oceanographic Institution (WHOI) scientists have discovered that bacterial communication could have a significant impact on the planet’s climate.
In the ocean, bacteria coalesce on tiny particles of carbon-rich detritus sinking through the depths. WHOI marine biogeochemists Laura Hmelo, Benjamin Van Mooy, and Tracy Mincer found that these bacteria send out chemical signals to discern if other bacteria are in the neighborhood. If enough of their cohorts are nearby, then bacteria en masse commence secreting enzymes that break up the carbon-containing molecules within the particles into more digestible bits. It has been suggested that coordinated expression of enzymes is very advantageous for bacteria on sinking particles, and Hmelo and her colleagues have uncovered the first proof of this in the ocean. (more…)
In the results of a new study, scientists explain how they used DNA to identify microbes present in the Gulf of Mexico following the Deepwater Horizon oil spill–and the particular microbes responsible for consuming natural gas immediately after the spill.
Water temperature played a key role in the way bacteria reacted to the spill, the researchers found. (more…)