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A New Way of Looking at Photosystem II

By Guest PostJune 14, 2012Sciencealgae, angstroms, bacteria, berkeley lab, carbon dioxide, catalytic cycle, critical formation, cryogenic freezing, electrochemical energy, electrons, femtosecond timescale, femtosecond x ray pulses, green, green plants, hydrogen atom, hydrogen ions, jan kern, junko yano, knowledge, lcls, microcrystals, nicholas sauter, oxidation states, oxygen molecules, paul adams, photooxidation, photosynthesis, photosystem ii, protein crystallography, proteins, protons, renewable energy, resolution, slac, solar energy, synchrotron radiation, terabytes of data, uwe bergmann, vittal yachandra, water, xray diffraction, xrays

Berkeley Lab and SLAC Researchers Study Key Protein Complex Crucial to Photosynthesis

Future prospects for clean, green, renewable energy may hinge upon our ability to mimic and improve upon photosynthesis – the process by which green plants, algae and some bacteria convert solar energy into electrochemical energy. An artificial version of photosynthesis, for example, could use sunlight to produce liquid fuels from nothing more than carbon dioxide and water. First, however, scientists need a better understanding of how a large complex of proteins, called photosystem II, is able to split water molecules into oxygen, electrons and hydrogen ions (protons). A new road to reaching this understanding has now been opened by an international team of researchers, led by scientists at the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and SLAC National Accelerator Laboratory.

Using ultrafast, intensely bright pulses of X-rays from SLAC’s Linac Coherent Light Source (LCLS), the research team produced the first ever images at room temperature of microcrystals of the photosystem II complex. Previous imaging studies, using X-rays generated via synchrotron radiation sources, required cryogenic freezing, which alters the samples. Also, to catalyze its reactions, photosystem II relies upon an enzyme that contains a manganese-calcium cluster that is highly sensitive to radiation. With the high-intensity femtosecond X-ray pulses of the LCLS, the research team was able to record intact images of these clusters before the radiation destroyed them. (more…)

Vampire Bat Study May Lead to Better Rabies-Control Strategies

By Guest PostJune 14, 2012Nature, ScienceAmazon rainforest, badgers, bat colonies, blood samples, bovine, cattle, charles rupprecht, culling bats, daniel streicker, ebola, genetic studies, immune, infectious diseases, ivan vargas, joel montgomery, jorge gomez benavides, marburg hemorrhagic fevers, mathematical modelling, nipah encephalitis, pejman rohani, peru, rabies, rabies in peru, rabies infections, rabies virus, sars, sergio recuenco, south america, tuberculosis, united states, university of michigan, vacuum effect, vampire bats, vampiricide, víctor pacheco, wildlife disease, zoonotic diseases

ANN ARBOR, Mich.— A new study of rabies in vampire bats in Peru has found that culling bats—a common rabies control strategy—does not reduce rates of rabies exposure in bat colonies, and may even be counterproductive.

The findings may eventually help public health and agriculture officials in Peru develop more effective methods for preventing rabies infections in humans and livestock, according to a team of scientists from the United States and Peru led by Daniel Streicker, a postdoctoral associate at the University of Georgia Odum School of Ecology.

The study was published online this week in the Proceedings of the Royal Society B. The research team includes University of Michigan population ecologist Pejman Rohani. (more…)

CU-Boulder-led Team Finds Microbes in Extreme Environment on South American Volcanoes

By Guest PostJune 13, 2012Scienceatacama mountain soil, fluorescent techniques, microbial species, rocky soils, south america, tallest volcanoes

A team led by the University of Colorado Boulder looking for organisms that eke out a living in some of the most inhospitable soils on Earth has found a hardy few. (more…)

A SMART(er) Way to Track Influenza

By Guest PostJune 12, 2012Scienceaartik sarma, amplification, andrew artenstein, anubhav tripathi, biological debris, brown assay, brown university, carmichael ong, DNA, first aid kit, flu detection test, genetic sequence, H1N1, hiv, influenza rna, influenza rna sequence, iPhone, magnetics, memorial hospital, microfluidics, nasba, nucleic acid sequence, pigs, polymerase chain reaction, prototype, rhode island, rna partners, rna probe, rna strand, smart, smart detector, stephanie mccalla, steven opal, swine flu, tb, tracking of influenza, tuberculosis, united states, virus in mexico

Brown University researchers have created a reliable and fast flu-detection test that can be carried in a first-aid kit. The novel prototype device isolates influenza RNA using a combination of magnetics and microfluidics, then amplifies and detects probes bound to the RNA. The technology could lead to real-time tracking of influenza. Results are published in the Journal of Molecular Diagnostics.

PROVIDENCE, R.I. [Brown University] — In April 2009, the world took notice as reports surfaced of a virus in Mexico that had mutated from pigs and was being passed from human to human. The H1N1 “swine flu,” as the virus was named, circulated worldwide, killing more than 18,000 people, according to the World Health Organization. The Centers for Disease Control and Prevention in the United States said it was the first global pandemic in more than four decades. (more…)

Mapping Volcanic Heat on Io

By Guest PostJune 11, 2012Scienceashley davies, bear fight institute, david williams, dennis matson, earth, erupting volcanoes, europa, floored volcanic craters, galileo mission, glenn veeder, heat flow, hot spots, io, jani radebaugh, journal icarus, jovian moon, life beyond earth, logarithmic scale, map, NASA, paterae, pattern of heat, thermal emission, torrence johnson, volcanic thermal emission, volcanoes

A new study finds that the pattern of heat coming from volcanoes on Io’s surface disposes of the generally-accepted model of internal heating. The heat pouring out of Io’s hundreds of erupting volcanoes indicates a complex, multi-layer source. These results come from data collected by NASA spacecraft and ground-based telescopes and appear in the June issue of the journal Icarus.

A map of hot spots, classified by the amount of heat being emitted, shows the global distribution and wide range of volcanic activity on Io. Most of Io’s eruptions dwarf their contemporaries on Earth. (more…)

Prize-Winning Mentor Menachem Elimelech Encourages a Life of Balance

By Guest PostJune 10, 2012Sciencecontrol water quality, creative researcher, energy efficient method, family friendly lab, menachem elimelech, prize winning mentor, troubleshoot experiments

When it comes to advising graduate students and postdoctoral scholars, Yale faculty member Menachem Elimelech believes his job isn’t rocket science. (more…)

NASA’s Spitzer Finds First Objects Burned Furiously

By Guest PostJune 9, 2012Sciencealexander sasha kashlinsky, ancient era, big bang, cosmic fuel, cosmic infrared background, expansion, faint objects, first objects, giovanni fazio, glenn wahlgren, harvey moseley, infrared wavelengths, james webb, john mather, los angeles, massive stars, matt ashby, mysterious sources, NASA, nearby universe, new york city, pattern of light, richard arendt, sky, space telescope, spitzer space telescope, ultraviolet wavelengths, universe, voracious black holes

PASADENA, Calif. — The faint, lumpy glow given off by the very first objects in the universe may have been detected with the best precision yet, using NASA’s Spitzer Space Telescope. These faint objects might be wildly massive stars or voracious black holes. They are too far away to be seen individually, but Spitzer has captured new, convincing evidence of what appears to be the collective pattern of their infrared light.

The observations help confirm the first objects were numerous in quantity and furiously burned cosmic fuel.

“These objects would have been tremendously bright,” said Alexander “Sasha” Kashlinsky of NASA’s Goddard Space Flight Center in Greenbelt, Md., lead author of a new paper appearing in The Astrophysical Journal. “We can’t yet directly rule out mysterious sources for this light that could be coming from our nearby universe, but it is now becoming increasingly likely that we are catching a glimpse of an ancient epoch. Spitzer is laying down a roadmap for NASA’s upcoming James Webb Telescope, which will tell us exactly what and where these first objects were.” (more…)

Building Molecular ‘Cages’ to Fight Disease

By Guest PostJune 9, 2012Scienceartificial vaccines, bioinformatics, biomedical engineering, building blocks, circulation, david baker, drug, drug delivery, duilio cascio, human like proteins, lego blocks, medicine, michael sawaya, molecular biology, molecular cages, molecular structure, nanoscale materials, neil king, puzzle pieces, specialized proteins, tangles of ribbon, three-dimensional, tiny structures, todd yeates, traditional vaccine, tumor cells, ucla, university of washington, virus derived proteins, yen ting lai

UCLA-created nanoscale protein containers could aid drug, vaccine delivery

UCLA biochemists have designed specialized proteins that assemble themselves to form tiny molecular cages hundreds of times smaller than a single cell. The creation of these miniature structures may be the first step toward developing new methods of drug delivery or even designing artificial vaccines.

“This is the first decisive demonstration of an approach that can be used to combine protein molecules together to create a whole array of nanoscale materials,” said Todd Yeates, a UCLA professor of chemistry and biochemistry and a member of the UCLA–DOE Institute of Genomics and Proteomics and the California NanoSystems Institute at UCLA. (more…)

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