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A self-powered biomolecular security system has been developed by US scientists. This could be used to encrypt financial, military, or other confidential information. Recent developments in the field of biocomputing have led to biomolecular systems that use chemical information to mimic digital electronics. Now Evgeny Katz and his team at Clarkson University, Potsdam, has taken the research a step further to make a keypad lock that powers itself using a biofuel cell. The biocatalyst system is composed of three enzyme-catalysed reaction steps, explains Katz. Enzymes are applied as input signals to trigger the biochemical reactions and only when applied in the correct...

Powerful anti-HIV drugs have come tantalizingly close to eradicating the virus from people, driving the blood level of HIV so low that standard tests cannot detect it. But no one has been cured: the virus comes roaring back in everyone who stops taking the drugs. A new study has identified one of HIV's main hideaways, raising intriguing possibilities about how to remove it. The work addresses a mystery first reported in 2006 by the lab of Robert Siliciano, a virologist at Johns Hopkins University in Baltimore, Maryland, who has developed the most sensitive test to find HIV. Siliciano's group first...

/Washington DC, USAs the athletes take centre stage at the Vancouver 2010 Winter Olympics and Paralympic Winter Games this month, chemists will be hard at work behind the scenes to catch athletes looking to win by taking drugs or blood products to artificially boost their performance during the competition.Doping is as old as the games - the ancient Greeks ate special diets and potions to enhance their athletic prowess - but over time, the practice has become considerably more sophisticated. Sports authorities began introducing drug testing in the 1970s and today, a variety of techniques exist in specialised anti-doping laboratories to catch...

Scientists in the United States have produced a simple dipstick test for detecting lead levels in paints. Easy-to-use biosensors are important for detection of highly toxic trace metal ions in the environment. Cross-linked gold nanoparticles modified with metal-specific DNAzymes have been used in solution to create highly sensitive and selective colorimetric metal sensors based on the colour change between aggregated (blue) and dispersed (red) gold nanoparticles. However, in solution the colour change can be difficult to distinguish and nanoparticle stability is poor, explains Yi Lu at the University of Illinois at Urbana Champaign. Lu and colleagues have developed a sensor that uses...

What revelations caused the biggest buzz in chemistry labs around the globe during 2009? With the help of an expert panel of journal editors, Chemistry World reviews the ground-breaking research and important trends of the year's published chemical science papers. Life in 3D DNA origami, the folding of DNA into shapes on the nanoscale, moved from 2D into 3D during 2009. Hao Yan's team at Arizona State University kicked off this craze with a tetrahedron shaped 3D container made of DNA.1 A day later, Danish researchers led by Kurt Gothelf, from Aarhus University, published details of a nanosized 3D DNA...

<p>The blueprint of a small organism's cellular machinery has been unveiled, offering the most comprehensive view yet of the molecular essentials of life. But the research also shows just how far biologists have to go before they understand the complete biochemical basis of even the simplest of creatures.</p>

Scientists in the US have discovered a new class of biological antifreeze molecules - the first that do not contain proteins. The antifreeze, extracted from an Alaskan beetle capable of surviving at -60°C, consists of linked mannopyranose and xylopyranose sugars, termed xylomannan, associated with a lipid. Large molecules that cause thermal hysteresis - a difference between the melting and freezing points of a solution - have been identified in many organisms that survive in the cold, from Antarctic fish to plants and bacteria. In all cases identified so far, thermal hysteresis appears to be caused by proteins, known as antifreeze proteins or...

NASA scientists studying the origin of life have reproduced uracil, a key component of our hereditary material, in the laboratory. They discovered that an ice sample containing pyrimidine exposed to ultraviolet radiation under space-like conditions produces this essential ingredient of life. Pyrimidine is a ring-shaped molecule made up of carbon and nitrogen and is the basic structure for uracil, part of a genetic code found in ribonucleic acid (RNA). RNA is central to protein synthesis, but has many other roles. "We have demonstrated for the first time that we can make uracil, a component of RNA, non-biologically in a laboratory...

Darwin’s theory that species originate via the natural selection of natural variation is correct in principle but wrong in numerous aspects of application. Speciation is not the result of an unlimited naturalistic process but of an intelligently designed system of built-in variation that is limited in scope to switching ON and OFF permutations and combinations of the built-in components. Kirschner and Gerhart’s facilitated variation theory provides enormous potential for rearrangement of the built-in regulatory components but it cannot switch ON components that do not exist. When applied to the grass family, facilitated variation theory can account for the diversification of...

US scientists are targeting an enzyme essential to bacterial metabolism in the search for new antibiotics.Michael Burkart of the University of California, San Diego, and Anton Simeonov from the National Institutes of Health, Bethesda, and coworkers have developed a high-throughput kinetic assay to screen small molecules as inhibitors of surfactin-type phosphopantetheinyl transferase (Sfp-PPTase) enzymes.Transferases are among a group of enzymes that can add and remove groups from proteins after their polypeptide backbone has been built - a process known as posttranslational modification. The enzymes are of biological and pharmaceutical interest as their inhibitors have been suggested as avenues for antibacterial,...

In a Commentary essay, Carl Woese and Nigel Goldenfeld provide an analysis of biological thought that differs profoundly from that presented by those celebrating the Bicentenary of Darwin's birth and, incidentally, the recently published AP Biology Standards. "This is the story of how biology of the 20th century neglected and otherwise mishandled the study of what is arguably the most important problem in all of science: the nature of the evolutionary process. This problem [ . . ] became the private domain of a quasi-scientific movement, who secreted it away in a morass of petty scholasticism, effectively disguising the fact...

Enlarge ImagePre-RNA? Hybrids between proteins and nucleic acids may have helped genetic molecules evolve.Credit: Science/AAAS Researchers pondering the origin of life have long struggled to crack the ultimate chicken-and-egg paradox. How did nucleic acids like DNA and RNA--which encode proteins--first form, when proteins are needed for their synthesis? Now, scientists report that they've cooked up molecular hybrids of proteins and nucleic acids that skirt the dreaded paradox. Although it's unknown whether such molecules existed prior to the emergence of life, they offer insight into a chemical pathway that might have helped life arise. DNA and RNA sport a backbone...

In my previous post I mentioned work by Pablo Debenedetti on ‘toy models’ of water. The places to look are: Buldyrev et al., PNAS 104, 20177 (2007) (here) for the solvation thermodynamics of ‘spherical’ water; and Patel et al., Biophys. J. 93, 4116 (2007) (here) and J. Chem. Phys. 128, 175102 (2008) (here) for water-explicit lattice models of proteins. And in discussing recent work on the mechanism of urea-induced protein denaturation, I neglected to mention Bruce Berne’s PNAS paper from late last year with Ruhong Zhou, Dave Thirumalai and Lan Hua (105, 16928; paper here). That paper on MD simulations...

I have been meaning for some time to write about an interesting paper in JACS by Naoki Sugimoto’s group in Kobe. It found its way into an article that I wrote this week for Nature’s online news. So I’ve decided to simply post this article here – it’s not all strictly relevant to water in biology, but hopefully is interesting stuff anyway. This is the version before editing, which has more detail. Shape might be one of the key factors in the function of mysterious ‘non-coding’ DNA. Everyone knows what DNA looks like. Its double helix decorates countless articles on...

Nuclear magnetic resonance spies the atomic details of proteins in action. Scientists have used NMR to look at proteins including TTHA1718 (above) inside living cells.Nature The atomic structures of proteins at work inside cells can now be probed, thanks to researchers who have modified a technique that is already widely used in labs and for medical imaging.When a protein is inside a cell — rather than in a test tube — it behaves subtly differently because it may be interacting with other biological molecules that float around in the cellular space. Because proteins are hard to work with unless they...

Enlarge ImageNot guilty. Plants don't appear to produce methane, as had been previously reported.Credit: Srimathy Sriskantharajah Plants do not make the powerful greenhouse gas methane, according to new research that contradicts a controversial finding made in 2006. Instead, plants appear to merely be passing gas, so to speak, originally made by soil microbes. Methane comes from a variety of sources, including gas leaks, forest fires, and, of course, cow burps. Microbes in wetland soil can produce methane anaerobically (without using oxygen), but the idea that it can be produced aerobically (using oxygen) by plants, and on a large scale,...

Sole member of world's first single-species ecosystem depends on rocks and radioactivity for life. The rod-shaped D. audaxviator was recovered from thousands of litres of water collected deep in the Mponeng Mine in South Africa.Greg Wanger, J. Craig Venter Institute / Gordon Southam, University of Western Ontario Nestled kilometres down in the hot, dark vaults of Earth's crust, scientists have discovered a remarkably lonely bacterium species. The rod-shaped bacterium, Candidatus Desulforudis audaxviator, lives independently of any other organism in a part of the Mponeng gold mine near Johannesburg, South Africa, some 2.8 kilometres beneath Earth's surface. There, water flows from...

Green fluorescent protein bags the biggest gong in science. Aequorea victoria, source of the green fluorescent protein.G. OCHOCKI/SCIENCE PHOTO LIBRARY The molecule responsible for a jellyfish's glow has won its discoverer and developers this year's Nobel Prize in Chemistry. The green fluorescent protein (GFP) has revolutionized medical and biological science by providing a way to track the activity of individual proteins within a living cell, and thereby monitor how genes are expressed. The prize is shared equally between three scientists: Osamu Shimomura, now an emeritus professor at the Marine Biological Laboratory in Woods Hole, Massachusetts, Martin Chalfie of Columbia University...

Students stabbed and set alight Two French research students found stabbed to death following a flat fire had been tied up and suffered horrific, excessive injuries, police have said. The bodies of Laurent Bonomo and Gabriel Ferez, both 23, were found in a ground-floor flat in New Cross, south-east London, on Sunday night. They had suffered a total of 243 stab wounds to the head, neck and chest before being set alight. The biochemistry students had been studying at Imperial College, London. Det Ch Insp Mick Duthie said he had no idea why the students were killed. Fiancee's tribute Speaking...

IN one sense we know much less about Earth than we do about Mars. The vast majority of life forms on our planet are still undiscovered, and their significance for our own species remains unknown. This gap in knowledge is a serious matter: we will never completely understand and preserve the living world around us at our present level of ignorance. We are flying blind into our environmental future. Since the Swedish naturalist Carl Linnaeus inaugurated the modern system of classification two and a half centuries ago, biologists have found and given Latinized names to about 1.8 million species of...