David W Deamer
|Division||Physical & Biological Sciences|
|Department||PBSci-Chemistry & Biochemistry Department|
|Office||Physical Sciences Building|
|Campus Mail Stop||Chemistry|
|1156 High Street|
Santa Cruz, CA
David Deamer's primary research area concerns the manner in which linear macromolecules traverse nanoscopic channels. Single-stranded nucleic acid molecules can be driven electrophoretically through a large channel embedded in a lipid-bilayer membrane, and the presence of the polynucleotide in the channel affects the ionic conductance in a manner related to chain length and concentration. This observation has considerable potential for characterizing DNA and RNA in microscopic volumes of nucleic acid solutions. (See Akeson et al. 1999 and Vercoutere et al. 2001 for recent reports.)
A second line of research concerns molecular self-assembly processes related to the structure and function of biological membranes, and particularly the origin and evolution of membrane structure. One example of such research was reported recently by Dworkin et al. (2001) in which it was shown that photochemical reactions simulating those occurring in the interstellar medium give rise to amphiphilic molecules that can self-assemble into membrane structures. Apel et al. (2001) and Monnard et al., (2002) went on to show that membranes can self-assemble for simple amphiphiles such as fatty acids and alcohols, and that such processes are markedly affected by ionic content of the environment. (See figure). These results help us to understand how primitive forms of cellular life appeared on the early Earth and were able to capture nutrients from the surrounding medium and incorporate them in intracellular growth processes.
Decanoic acid is a simple amphiphilic molecule that can assemble into membranous vesicles such as those shown above on the left. However, in the presence of salt solutions such as sea water, the vesicles collapse and aggregate, suggesting that the membranes of the first cellular life required a fresh-water environment for stability. Monnard et al. 2002.
Biography, Education and Training
B.S., Duke University
Ph.D., Ohio State University School of Medicine
Honors, Awards and Grants
Guggenheim Fellow 1986
President, ISSOL 2011 - present
- J. P. Dworkin, D. W. Deamer, S. A. Sandford, and L. J. Allamandola. 2001. Self-assembling amphiphilic molecules: Synthesis in simulated interstellar/precometary ices. Proc. Natl. Acad. Sci. USA 98:815-819.
- Vercoutere, W., S. Winters-Hilt, H. Olsen, D.W. Deamer. D. Haussler, and M. Akeson. 2001. Rapid discrimination among individual DNA molecules at single nucleotide resolution using a nanopore instrument. Nature Biotechnology 19: 248-250.
- Deamer D, Dworkin JP, Sandford SA, Bernstein MP, Allamandola LJ. The first cell membranes. 2002. Astrobiology. 2:371-81.
- Winters-Hilt, S., W. Vercoutere, V. S. DeGuzman, D. Deamer, M. Akeson & D. Haussler. 2003. Highly accurate classification of Watson-Crick base-pairs on termini of single DNA molecules Biophys. J. 84:967-76.
- Vercoutere, W.A., S. Winters-Hilt, V. S. DeGuzman, D. Deamer, S. Ridino, J. T. Rodgers, H. E. Olsen, A. Marziali, and M. Akeson. 2003. Discrimination among individual Watson-Crick base-pairs at the termini of single DNA hairpin molecules. Nucleic Acids Research 31:1311-1318.