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Nature's atmospheric cleanup scrubs up well for The Alchemist, while the biochemistry of opium poppies turns out to be less than painful and a genetic heart study reveals a more critical role for triglycerides. In catalysis, we learn of a multitasking organometallic iron compound. In space chemistry we hear about propylene on Titan. Finally, more bio at the Nobels.




Scientists in Germany have demonstrated for the first time how isoprene - an important natural hydrocarbon emitted by trees is decomposed by hydroxyl (OH) radicals in the atmosphere. OH radicals have been referred to colloquially as the detergent of the atmosphere. The atmosphere has an astonishing ability to cleanse itself with various chemical processes ensuring that trace gases and pollutants are removed from the atmosphere. Now, Hendrik Fuchs of the Jülich research center and colleagues have figured out a reaction mechanism that explains the measured atmospheric concentrations of isoprene and hydroxyl radicals in the air above large North American forests and tropical rainforests. Isoprene oxidation results in generation of peroxy radicals, which then regenerate hydroxyl radicals, the team says. They admit that the actual concentrations require an additional OH source to explain the high concentrations observed despite the presence of hydrocarbons.





Metabolic enzymes in opium poppies - Papaver somniferum - multitask when playing their part in the biosynthesis of morphine, codeine and other important opioids, researchers at the University of Calgary have found. The insights could be exploited by the biotech industry hoping to manipulate the biochemical pathways involved and create varieties of opium poppy that produce higher levels of specific drugs. It may eventually be possible to manipulate metabolic pathways so that other plants - or even yeast and bacteria - can produce morphine, codeine or thebaine, an intermediate compound obtained only from opium poppy and used to make the painkiller drug oxycodone, the team reports in the Journal of Biological Chemistry.





A global hunt for genes that influence heart disease risk has uncovered 157 changes in human DNA that alter the levels of cholesterol and other blood fats – a discovery that could lead to new medications. The work points to an important role for triglycerides in cardiovascular disease. The results, published in two new papers appearing simultaneously in the journal Nature Genetics, come from the Global Lipids Genetics Consortium -- a worldwide team of scientists who pooled genetic and clinical information from more than 188,000 people from many countries and heritages.





US researchers have demonstrated a small-complex metal catalyst that acts like a multifunctional enzyme mimic. The new catalyst can oxidize specific C-H bonds on many different targets. This will greatly streamline the process of modifying known molecules in new ways, a key part of drug discovery, says Christina White of the University of Illinois. The new catalyst, iron CF3-PDP, can accomplish in half an hour chemical transformations that would otherwise take months. The approach to designing this novel catalyst could be applicable to other catalysts for C-H activation, the team reports in the Journal of the American Chemical Society.





The list of organic molecules to be found in space grows annually. Now NASA's Cassini probe has spotted the chemical signature of propylene on Saturn's moon Titan. Much of the media talked of this small molecule being an ingredient of plastic, which it is in the sense that it is the monomer for producing polypropylene, but of course, the discovery is much more subtle. Infrared spectroscopy revealed the presence of this small molecule and details are published in Astrophysical Journal Letters. Titan's atmosphere is rich in nitrogen and the simplest hydrocarbon methane. Solar energy, however, can form reactive species that recombine to form ethane, propane and now we know propylene. But, Cassini's plasma spectrometer has revealed that there are hydrocarbons present with masses of many thousands of Daltons.





The 2013 Nobel Prize in Physiology or Medicine was awarded to James E. Rothman, Randy W. Schekman and Thomas C. Südhof for their discoveries of machinery regulating vesicle traffic, a major transport system in our cells. The scientists essentially solved the mystery of how the cell organizes its transport system. Each cell is a factory that produces and exports molecules. For instance, insulin is manufactured and released into the blood and chemical signals called neurotransmitters are sent from one nerve cell to another. These molecules are transported around the cell in small packages called vesicles. The three Nobel Laureates have discovered the molecular principles that govern how this cargo is delivered to the right place at the right time in the cell.