First to fall under The Alchemist's gaze this week is Korean work into coating yeast particles with a protective silica shell to stabilize the organism for new lines of research. Geochemistry billions of years old reveals a sulfidic past and answers questions about how the Earth got its oxygen-rich atmosphere. In biophysical chemistry, US scientists have found a way to extend the redox range of copper-containing proteins and in computational chemistry Dutch scientists explain precisely how hydrogen interacts with copper surfaces. Good news for those fearful of mercury dental fillings, as a new composite material emerges from polymer and nanochemistry research. Finally, a cash injection from US recovery funds could see the establishment of yet another "Facebook for scientists", only this time it's aimed squarely at American institutions.
Researchers in Korea have found a way to give yeast particles a hard shell composed of silicon dioxide. By coating Saccharomyces cerevisiae with a protective, synthetic shell, Insung Choi and colleagues can triple the life of the yeast and also block replication. Previous researchers have coated yeast with a phosphate layer, but the current biomimetic approach could open up new avenues of research for this favorite organism of molecular biology.
New research from geoscientists at the University of California, Riverside, corroborates recent evidence about the Great Oxidation Event. It has thus helped solve some outstanding questions surrounding the theory that the Earth's atmosphere underwent a dramatic rise in oxygen 2.4 billion years ago. An analysis of 2.5 billion-year-old black shales from Western Australia add to the evidence that oxygen production began in the Earth's oceans at least 100 million years before the GOE. The findings, which bring to light sulfidic conditions, could also have implications for understanding other geologic periods.
Tailor-made proteins for applications such as artificial photosynthetic centers, long-range electron transfers, and fuel-cell catalysts for energy conversion might be possible thanks to advances in natural redox processes. Yi Lu of the University of Illinois and colleagues have shown that hydrophobic interactions and hydrogen bonding can be exploited to fine-tune the redox potential of copper-containing cupredoxin proteins. "We have now extended the range both above and below what had previously been found in nature," Lu says.
An international team led by chemists at Leiden University in The Netherlands have demonstrated that computers can now be used to make accurate predictions of the reactions of hydrogen molecules with surfaces. The team has developed a new method for modeling what happens when hydrogen molecules separate on a copper surface. The researchers suggest that the way is now open for calculating the interaction between more complex molecules and surfaces. Understanding the interaction of hydrogen with a metal surface is an important aspect of developing hydrogen storage materials for future "clean" power devices, such as fuel cells.
Current dental fillings to replace damaged tooth enamel are based mainly on nineteenth century technology of mercury amalgams. The familiar silvery-black fillings that so many people have could soon be a thing of the past, thanks to the development of a tough material for twenty-first century dentistry. Kent Coulter and his colleagues at Southwest Research Institute in San Antonio have developed a new proof-of-concept dental restorative material based on zirconia nanoplatelets trapped in a polymer matrix. The material is produced in rolls, which could be cut to fit, packed into a cavity and then cured with ultraviolet light to form hard, long-lasting, and light-colored filling.
Look Ma, No Mercury in Fillings!
A cash injection of $12.2 million from the American Recovery and Reinvestment Act of 2009 could help The University of Florida, Cornell University and a handful of other schools build a social media site for scientists. "The goal of the program is national networking of all scientists," explains Michael Conlon, interim director of biomedical informatics for the University of Florida. Initially, the network will hook together seven institutions but could later be rolled out across the USA. Critics have pointed out that science is an international effort and that such a parochial system could unnecessarily exclude scientific talent and creativity from across the globe.