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.
Measurements taken at the molecular scale have, for the first time, confirmed a key property that could improve our knowledge of how the heart and lungs function. Univ. of Washington researchers have shown that a favorable electrical property is present in a type of protein found in organs that repeatedly stretch and retract, such as the lungs, heart and arteries.
The molecular building blocks that make up DNA absorb ultraviolet light so strongly that sunlight should deactivate them, yet it does not. Now, scientists at SLAC National Accelerator Laboratory have made detailed observations of a “relaxation response” that protects these molecules, and the genetic information they encode, from UV damage.
Ribosomes are responsible for the production of the wide variety of proteins that include enzymes. But until now researchers had not uncovered all of the details of how the proteins that are used to construct ribosomes are themselves produced. Biologists in California now say they have found the “missing link” in the chemical system that allows ribosomal proteins to be synthesized.
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.
HIV-1, the virus responsible for most cases of AIDS, is a very selective virus. It doesn’t readily infect species other than its usual hosts. While this would qualify as good news for most mammals, for humans this fact has made the search for effective treatments and vaccines for AIDS that much more difficult; without an accurate animal model of the disease, researchers have had few options for clinical studies of the virus.
Think of the human body as an intricate machine whose working parts are proteins: molecules that change shape to enable our organs and tissues to perform tasks such as breathing, eating or thinking. Of the millions of proteins, 500 in the kinase family are particularly important to drug discovery. Kinases are messengers: They deliver signals that regulate and orchestrate the actions of other proteins.
Researchers from North Carolina State Univ. have developed a technique to control populations of the Australian sheep blowfly—a major livestock pest in Australia and New Zealand—by making female flies dependent upon a common antibiotic to survive.
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.
Nanoengineers at UC San Diego have developed a nanoshell to protect foreign enzymes used to starve cancer cells as part of chemotherapy. Enzymes are naturally smart machines that are responsible for many complex functions and chemical reactions in biology. However, despite their huge potential, their use in medicine has been limited by the immune system, which is designed to attack foreign intruders.
How does a stem cell decide what path to take? In a way, it’s up to the wisdom of the crowd. The DNA in a pluripotent stem cell is bombarded with waves of proteins whose ebb and flow nudge the cell toward becoming blood, bone, skin or organs. A new theory by scientists at Rice Univ. shows the cell’s journey is neither a simple step-by-step process nor all random.
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.
After a large stroke, motor skills barely improve, even with rehabilitation. An experiment conducted on rats demonstrates that a course of therapy combining the stimulation of nerve fiber growth with drugs and motor training can be successful. The key, however, is the correct sequence: Paralyzed animals only make an almost complete recovery if the training is delayed until after the growth promoting drugs have been administered.
Researchers at the Univ. of Tennessee (UT) are a step closer to creating a prophylactic drug that would neutralize the deadly effects of the chemical weapons used in Syria and elsewhere. Jeremy Smith, UT-ORNL Governor’s Chair and an expert in computational biology, is part of the team that is trying to engineer enzymes—called bioscavengers—so they work more efficiently against chemical weapons.
Why would already abundant “natural killer” cells proliferate even further after subduing an infection? It’s been a biological mystery for 30 years. But now Brown Univ. scientists have an answer: After proliferation, the cells switch from marshaling the immune response to calming it down.
Scientists seeking ways to engineer the assembly of tiny particles measuring just billionths of a meter have achieved a new first: the formation of a single layer of nanoparticles on a liquid surface where the properties of the layer can be easily switched. Understanding the assembly of such nanostructured thin films could lead to the design of new kinds of membranes with a variable mechanical response for a wide range of applications.
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.
An international collaboration of researchers have sequenced and analyzed the genome of the common bean to begin to identify genes involved in critical traits such as size, flavor, disease resistance and drought tolerance. They learned that, unlike most other food crops, the common bean was domesticated twice by humans about 8,000 years ago. The results of the study may help guide modern breeding programs.
Scientists in Switzerland have invented a molecule that can easily and quickly show how much drug is in a patient’s system. All that is needed to perform accurate measurements is a conventional digital camera. The result of innovative protein engineering and organic chemistry, the molecule has been shown to work on a range of common drugs for cancer, epilepsy and immunosuppression.
Sometimes a cell has to die—when it's done with its job or inflicted with injury that could otherwise harm an organism. Conversely, cells that refuse to die when expected can lead to cancer. So scientists interested in fighting cancer have been keenly interested in learning the details of "programmed cell death." They want to understand what happens when this process goes awry and identify new targets for anticancer drugs.
When stem cells are used to regenerate bone tissue, many wind up migrating away from the repair site, which disrupts the healing process. But a technique employed by a Univ. of Rochester research team keeps the stem cells in place, resulting in faster and better tissue regeneration. The keyis encasing the stem cells in polymers that attract water and disappear when their work is done.
Scientists from Lawrence Berkeley National Laboratory have gained more insights into why older women are more susceptible to breast cancer. They found that as women age, the cells responsible for maintaining healthy breast tissue stop responding to their immediate surroundings, including mechanical cues that should prompt them to suppress nearby tumors.
In the last few years, the benefits of short, intense workouts have been extolled by both researchers and exercise fans as something of a metabolic panacea capable of providing greater overall fitness. Now, a new study from scientists at The Scripps Research Institute in Florida confirm that there is something molecularly unique about intense exercise: the activation of a single protein.
Cancer is a group of diseases characterized by uncontrolled growth and spread of abnormal cells. The disease can be caused by both external and internal factors; and, if the spread isn’t controlled, it can result in death. The annual cancer statistics report from the American Cancer Society estimates there will be 1,885,540 new cancer cases and 585,720 cancer deaths in the U.S. for 2014.