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SSRL Researchers Map Transporter Structure
symmetry Gallery: Ben Laposky
Al Ashley Fellowship Proposals Due June 15

SLAC Today

Friday - May 25, 2007

SSRL Researchers Map Transporter Structure

The transporter structure.

Researchers are one step closer to understanding how cells receive nutrients and dispose of toxins. The study could eventually lead to more efficient drugs and new antibiotics.

Proteins embedded on the surface of cells called ATP-Binding Cassette (ABC) transporters are responsible for moving nutrients and waste across cell membranes. The process of active transport uses the energy from bound adenosine triphosphate (ATP), a chemical compound that transports chemical energy, to "pump" nutrients against the concentration gradient. One such ABC transporter, HI1470/1, was recently studied in crystal form at the Stanford Synchrotron Radiation Laboratory's Beamline 9-2.

Although the mechanism of transport is not completely understood, it is believed that ATP binding causes the transporter to undergo a structural change, carrying the molecule across the membrane in the process. Five years ago the structure of a similar transporter known as BtuCD was solved. At SSRL, a group of scientists from Caltech have now solved the structure of HI1470/1 in a conformation that differs from that of BtuCD.

When the mapped structures of the two transporters were compared, subtle differences, including minor twists and rotations of the membrane spanning region were found. These variations will help researchers better understand the transporting process.

In the future, scientists may be able to use this knowledge to develop inhibitors that stop similar transporter proteins from carrying medicines out of cells, thereby increasing the efficiency of drugs. In addition, antibiotics could be produced to stop harmful bacteria from receiving nutrients from transporters, effectively starving the unwanted visitor.

symmetry Gallery:
Ben Laposky

A boxy cathode-ray oscilloscope, covered with buttons and knobs and meters and lights, looks like something you know you shouldn't touch. The versatile electronic testing and analysis device—used as a prop in 1950s and '60s television and film to signal that science was being done—could double as a robot's midsection. It seems unlikely that someone could create wild gyrations of dancing light with such an unromantic instrument. But that's exactly what artist Ben Laposky did, creating some of the first graphic images generated by machine.

Laposky was a draftsman, a lettering artist, and a long-time student of mathematics who owned a sign shop in Iowa and dabbled in art in his spare time. Inspired by futuristic literature that envisioned "painting with light," he began turning undulating light from an oscilloscope into an electric trance dance. For 16 years beginning in 1950, he used the machine to manipulate basic waves into elegantly rhythmic designs he called "oscillons."  Read more...

Al Ashley Fellowship Proposals Due June 15

(Photo - Al Ashley)Applications for the Alonzo W. Ashley Career Development Fellowship are due on June 15, 2007. Don't miss this opportunity to further develop your career while contributing to the mission of the lab.

The fellowship was created in 1999 in honor of Al Ashley, who promoted diversity and encouraged career development for employees and career exploration for talented students during his 30 years of service to SLAC.

The one-year fellowship can help employees develop and implement programs and projects, explore new job opportunities, and take time off to further their education.

This fellowship must take place between October 1, 2007 and September 30, 2008. To be eligible, you must:
- Have been a SLAC employee for
  at least three years
- Have a demonstrated interest in
  promoting diversity at work or in
  the community
- Be able to manage time
- Have your supervisor's approval

More information...

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