Tuesday, March 17, 2009
Colleagues Celebrate Bothner-By’s Work in NMR Spectroscopy
Aksel Bothner-By (right) and Josef Dadok
Fifty years ago, NMR spectroscopy was a young field, with spectroscopists spread across the country. They wanted to meet with each other to share their ideas, and Emeritus Professor Aksel Bothner-By was one of the men who got the ball rolling.
Bothner-By and his colleague Barry Shapiro hosted the second through 11th Experimental NMR Conference (ENC) at the Mellon Institute. At the end of March, the NMR community is gathering in Asilomar, Calif., to celebrate the 50th anniversary of the ENC. At age 88, unable to travel to California for this year’s ENC, Bothner-By’s colleagues at Carnegie Mellon are hosting a symposium in his honor.
“Aksel was an important figure in the NMR community for decades. He developed key tools for NMR analysis that are now used routinely by scientists all over the world,” said Roberto Gil, associate research professor of chemistry, director of the Department of Chemistry NMR Facility and co-organizer of the symposium.
Bothner-By, now an emeritus professor of chemistry, came to Carnegie Mellon in 1958, when NMR spectroscopy was an up-and-coming field. NMR spectroscopy, an analytical technique that provides information about the structure of chemical and biochemical compounds, takes advantage of a physical phenomenon called nuclear magnetic resonance (NMR) occurring inside an atom’s nucleus. In a magnetic field, some nuclei wobble and spin like tops, emitting a radio frequency signal. By observing the behavior of these spinning nuclei when they are exposed to a magnetic field and pulses of radio waves, scientists can piece together the chemical structure of the compound.
During his 33 years at Carnegie Mellon, Bothner-By conducted numerous experiments that advanced NMR spectroscopy. In the 1960s, he and Salvatore Castellano developed a computational method for analyzing NMR spectra, which later became the computer program LAOCN3 that was widely used by NMR spectroscopists worldwide. In the late ’60s, Bothner-By and Josef Dadok, now an emeritus professor of chemistry at Carnegie Mellon, built a multinuclear NMR spectrometer with a superconducting magnet operating at 250 MHz. It became the workhorse of Carnegie Mellon’s NMR Facility for Biomedical Studies.
“The number of publications produced by users of this facility was quite impressive,” said Dadok, who headed the technical side of the spectrometer project.
Although the 250 MHz spectrometer was an extraordinary instrument at the time, in 1976 Bothner-By and Dadok set their sights higher. In collaboration with Intermagnetics General Corporation, Bothner-By led the team that built the world’s first 600 MHz spectrometer, which reigned as the world’s most powerful system for several years. At that time, many scientists all over the world wanted to have their samples analyzed with the 600 MHz spectrometer. The best and brightest NMR spectroscopists flocked to Carnegie Mellon to analyze everything from natural products to DNA, RNA and proteins.
For Bothner-By, the high magnetic field posed a challenge. He should have been able to glean more information about the molecules he was studying, but he was having trouble getting a key type of information about a certain class of larger molecules. Taking inspiration from his wife, a figure skater, he developed the CAMELSPIN experiment. Now called ROESY, the technique allows scientists to acquire this key type of information in mid-size molecules like small peptides using NMR regardless of the molecules’ size or the strength of the magnet.
During his career, Bothner-By published more than 150 papers, mostly in the field of NMR spectroscopy. In 2002, he was one of three recipients of the Günther Laukien Prize for his efforts to develop techniques to measure residual dipolar couplings (RDCs). This work allowed scientists to analyze biomolecules with greater precision than ever before, according to Gil.
“Aksel is a visionary,” Gil said. “His work is an inspiration to me and to so many others in the NMR community.”
Reprinted from the March 2009 issue of the Piper
By: Amy Pavlak