The Alchemist Newsletter: January 8, 2008

Environmental research gets a boost from NIH in the form of a $6.8 million grant to establish three DISCOVER centers to study the effects of environmental pollutants. Crystallography reveals the cellular machinations of the humble hydrogen peroxide molecule in The Alchemist this week, while fatty samples suggest that all of us harbor at least one pesticide or other persistent organic compound in our tissues. In environmental news, researchers have turned to gold to help them convert biomass into a useful chemical feedstock, while in theoretical studies it still matters, relatively, that electrons and nuclei are massively and speedily different. Finally, crystals behaving badly in supramolecular chemistry could herald new approaches to technological problems.

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Environmentally granted

Almost $7 milllion is to be made available by the National Institute of Environmental Health Sciences (NIEHS), part of the National Institutes of Health for the creation of three new research centers known as DISCOVER - Disease Investigation Through Specialized Clinically-Oriented Ventures in Environmental Research. "The DISCOVER centers will help to define the role of environmental agents in the initiation and progression of human disease and develop new ways to both prevent and treat disease," explains interim director Dennis Lang of the NIEHS Division of Extramural Research and Training, "The potential impact of the research that these three centers will be conducting is enormous."

NIEHS Awards DISCOVER Grants

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H2O2 and all that

The apparently simple molecule hydrogen peroxide plays a complex role in health. Now, researchers at Wake Forest University School of Medicine have uncovered how H2O2 plays its part. For example, when the immune system is activated in response to the presence of bacteria, large amounts of hydrogen peroxide are released by certain cells to fight the infection. Now, Todd Lowther and colleagues have obtained a crystal structure that shows how two proteins produced by cells interact to regulate the levels of hydrogen peroxide. The research could help us understand what goes wrong in certain disease states and may lead ultimately to new avenues for therapy in a range of diseases.

Hydrogen Peroxide Has A Complex Role In Cell Health

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Global contamination

It is possible that all of us are contaminated with at least one pesticide or other persistent organic compound residue, according to Spanish researchers. A study carried out by researchers from the Department of Radiology and Physical Medicine of the University of Granada, in collaboration with the Andalusian School of Public Health showed that 100% of volunteers tested in Spain tested positive for at least one persistent organic compound (POC). Juan Pedro Arrebola Moreno and colleagues measured the contamination levels of POC, including the fungicide hexachlorobenzene, DDE (a DDT metabolite) in almost 400 adults from an urban and a semi-rural region. 100% of subjects had DDE in their bodies. Polychlorinated biphenyls were seen at detectable levels in around 90% of the volunteers.

100 percent of people carry at least 1 type of pesticide

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Gold into black gold

A gold catalyst can help convert biomass into methyl esters for use as an alternative chemical industry feedstock to compliment or even displace petroleum-derived compounds. Claus Christensen and colleagues in the Center for Sustainable & Green Chemistry at the Technical University of Denmark, in Lyngby, have developed a selective gold-catalyst for the oxidation of furfural and hydroxymethylfurfural into their respective methyl esters. The researchers used sodium methoxide in methanol solvent, an oxygen atmosphere, and gold deposited on titania nanoparticles to efficiently convert the hydroxyl and/or aldehyde groups of the starting materials to the end product. Methyl furoate formed from furfural is useful for flavor and fragrance applications and potentially as an industrial solvent. Furandimethylcarboxylate derived from hydroxymethylfurfural is a monomer that can replace terephthalic acid in plastics, the researchers say.

Gold Catalyst Mediates Transformation Of Biomass Feedstocks

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Born-Oppenheimer rescued

A key assumption of theoretical chemistry was under threat, but has been brought back from the brink by US scientists. The Born-Oppenheimer approximation states that electrons move so fast compared with atomic nuclei that the motion of each can be treated separately in quantum mechanics. However, researchers in Taiwan provided startling evidence that the approximation fails catastrophically under certain conditions which could have lead to the unraveling of much of theoretical chemistry. Now, Etienne Garand of the University of California, Berkeley, and co-workers have demonstrated that the Born-Oppenheimer approximation holds good for the chlorine-hydrogen system and conventional quantum wisdom is saved.

Key plank of theoretical chemistry rescued

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Crystals behaving badly

Rule-bending crystals that do not have the usual periodicity of their well-behaved counterparts reveal peculiar host-guest chemistry, according to research published in the January 4 issue of the journal Science. Mark Hollingsworth of Kansas State University and colleagues looked at how urea molecules form tunnels around nonadecane molecules, to produce a double-helical honeycomb-like structure. In general, such complexes would have a regular, repeating structure, but aperiodic crystals do form in which the host and guest don not match perfectly. The researchers have found that the effects of this bad behavior is most apparent in their phase transitions during which the interaction between host and guest can change without their being any noticeable change in the host and guest molecules themselves.

Strange-behaving crystals could have impact on research, technology

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-- David Bradley, Science Journalist