The Alchemist Newsletter: October 18, 2005

In this issue, The Alchemist turns his attention on Nobel laureates, marine antibiotics, molecules of light, growing a DNA forest, and low-energy alloys.

	organic: Nobel chemists
	pharma: Fishing for antibiotics
	physical: Making light work of molecules
	biotech: The forest of DNA
	materials: Hardened magnesium cuts energy costs

Nobel chemists

This year's Nobel Prize for Chemistry was awarded to three chemists from the US and France for their pioneering work on metathesis - one of organic chemistry's most important reactions. Yves Chauvin of the Institut Français du Pétrole, Rueil-Malmaison, France, Robert H. Grubbs of California Institute of Technology (Caltech), Pasadena, CA, USA, and Richard R. Schrock of the Massachusetts Institute of Technology (MIT), Cambridge, MA, USA, this year share the Prize equally "for the development of the metathesis method in organic synthesis". Their work has led to new routes to a vast range of compounds, such as the pharmaceuticals, agrochemicals, and other materials, and has greater potential yet limited only by the chemist's imagination.

Metathesis - a change-your-partners dance

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Fishing for antibiotics

Ten new natural products from a seaweed found in the waters off Fiji offer new hope in the fight against disease. Researchers at Georgia Institute of Technology have demonstrated that these diterpene benzoates have activity against cancer cells, bacteria, and HIV. Indeed, two of them are effective against antibiotic-resistant Staphylococcus aureus at usefully low concentrations. Julia Kubanek and colleagues explain that the work is only at the "test-tube level" so far, however, although pharmaceutical giant Bristol Myers Squibb is working with the team on the anticancer potential of several of the compounds.

Coral Reef Remedies

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Making light work of molecules

Molecules are not all about atoms, at least according to research from the University of Rostock, Germany, where physicists have created "molecules" using pulses of light. Such light molecules might lead to significant increases in data transfer rates for optical communications technology. The atoms in the light molecules created by Fedor Mitschke and colleagues are temporal solitons, pulses of light that do not dissipate rapidly and retain their shape. These persistent solitons could thus carry data over greater distances without degradation than is currently possible. This is the first time scientists have made temporal solitons stick together to form structures analogous to molecules.

Molecules of light pulses

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The forest of DNA

Vertical strands of DNA can be constructed using the enzyme TdTase, terminal deoxynucleotidyl transferase, according to US scientists. Ashutosh Chilkoti and colleagues at Duke University start with a forest of short DNA strands on nanoscale patches of gold, lithographed on to a silicon surface. They then employ TdTase and a cobalt catalyst to adds nucleotide building blocks to the tops of the DNA forest, extending the forest canopy. Chilkoti suggests that the development of this and related technology will ultimately enable bio-manufacturing possible at an industrial scale.

Engineers build DNA 'nanotowers' with enzyme tools

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Hardened magnesium cuts energy costs

Magnesium alloys are being used increasingly in engineering applications because of their relatively low density, which means lower energy consumption. Katsuyoshi Kondoh, Ritsuko Tsuzuki, and Eiji Yuasa of the Research Center for Advanced Science and Technology, University of Tokyo, investigated the effects of adding Mg₂Si dispersoids to magnesium alloys and observed a significant improvement in wear resistance and tribological properties, and reduce friction between the alloy surface and other materials.

Tribological Properties of Magnesium Matrix Composite Alloys Dispersed with Mg2Si Particles

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-- David Bradley, Science Journalist