- Number 382 |
- February 18, 2013
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New look at cell membrane reveals surprising organization
A new way of looking at a cell's surface reveals the distribution of small molecules in the cell membrane, changing the understanding of its organization.
A novel imaging study by researchers from DOE's Lawrence Livermore National Laboratory, the University of Illinois and the National Institutes of Health revealed some unexpected relationships among molecules within cell membranes.
Their findings provide a new way of studying cell structure and ultimately its function.
Led by Mary Kraft of the University of Illinois, Peter Weber of Lawrence Livermore National Laboratory and Joshua Zimmerberg of the National Institutes of Health, the team published their findings in the online version of the Jan. 28 edition of the Proceedings of the National Academy of Sciences. -
The motor that drives Archaea
The protein structure of the motor that propels Archaea – the third domain of life, along with Bacteria and Eukarya – has been characterized for the first time by a team from DOE’s Lawrence Berkeley National Laboratory and Germany’s Max Planck Institute for Terrestrial Microbiology.
The researchers, led by Sonja-Verena Albers of the Max Planck Institute and John Tainer of Berkeley Lab’s Life Sciences Division and the Scripps Research Institute, call this unique motor an archaellum. It functions like a bacterial flagellum, a whip-like rotating propeller, but structurally it more closely resembles the Type 4 pilus, the filamentary “grappling hook” by which bacteria attach to surfaces and pull themselves along.
Genetic modifications of the extremophile S. acidocaldarius in the Albers lab pinpointed the FlaI (“flah-eye”) protein as responsible for assembling the archaellum and making it rotate. Sophia Reindl of Tainer’s lab crystallized the protein and used beamline 8.3.1 at Berkeley Lab’s Advanced Light Source (ALS) to do x-ray crystallography, which revealed that FlaI consists of two parts, a globular base connected to a moveable tip by a flexible linker. -
Fuels synthesis insight can reduce costs and greenhouse gases
Scientists at DOE's Los Alamos National Laboratory made a major step forward recently towards transforming biomass-derived molecules into fuels. The team elucidated the chemical mechanism of the critical steps, which can be performed under relatively mild, energy-efficient conditions. The journal Catalysis Science & Technology published the research.
Trash to Treasure
“Efficient conversion of non-food biomass into fuels and chemical feedstocks could reduce society’s dependence on foreign oil and ensure the long-term availability of renewable materials for consumer products,” said John Gordon, one of the senior Los Alamos scientists on the project. -
US toroidal field conductor fabrication advances
US ITER and its vendors are moving into a new fabrication phase for the toroidal field magnet system in the international ITER fusion reactor. Cabling and conductor fabrication are now underway in New Hampshire and Florida for the niobium-tin wire produced in the US. All of this fabrication effort is in preparation for delivering the final product in 2015 to the European Union.
As part of its contributions to the ITER project, the United States is producing over 4 miles of cable-in-conduit superconductor; other ITER partners will provide the remainder of the conductor. This conductor will encircle the ITER tokamak in a toroidal pattern, providing immense magnetic fields for confining 150 million degree plasma into a doughnut-like shape.