B.Phil. thesis Defense, Friday, April 25, 2003,
12:00 PM, Allen Hall, Room 216
"Biomolecules in the Gas Phase. High Resolution Ultraviolet Spectroscopy of DNA
Bases and Base Pair Analogs" (The B.Phil. thesis is the undergraduate
Honors thesis. If it is successfully defended, Rob's B.Phil. will be the first
in the history of the Department.) All are welcome to attend.
Commitee Members:
Dr. David W. Pratt (Advisor)
Dr. Peter E. Siska
Dr. John Rosenberg (biology)
Dr. Alec Stewart (Physics and Dean of the Honors College)
BIOMOLECULES IN THE GAS PHASE. HIGH RESOLUTION ULTRAVIOLET SPECTROSCOPY OF DNA BASES AND BASE PAIR ANALOGS
Abstract:
Information about the geometries, hydrogen bonding motifs, and proton transfer tunneling dynamics in several base pair analogs has been obtained using the technique of high resolution electronic spectroscopy in the gas phase. The systems studied include 2-hydroxypyridine (2HP), 2-pyridone(2PY), 2-aminopyridine (2AP), and dimers formed by co-expansion of the component parts in a molecular beam, including 2HP/2PY and 2AP/2PY, the analog of the well-known A/T base pair found in DNA. Tunneling has been observed in the spectrum of 2HP/2PY and probed using deuterium labeling methods. A Watson-Crick configuration is found in 2AP/2PY. The N…H-N and N-H…O hydrogen bond lengths have been determined from the measured moments of inertia. Additionally, the two bases are found not to be co-planar, leading to a "pro-chirality" when they are joined together.