Professor Emeritus of Chemistry at the University of California at Santa Cruz.
Membrane Biophysics, Model Membrane Systems, Membrane Transport Mechanisms, Molecular Self-Assembly Processes.
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. These results help 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.
Akeson, M., D. Branton, J.J. Kasianowicz, E. Brandin, and D.W. Deamer. 1999. Microsecond time-scale discrimination among polycytidylic acid, polyadenylic acid, and polyuridylic acid as homopolymers or as segments within single RNA molecules. Biophys. J. 77: 3227-3233.
Apel. C., M. Mautner and D.W. Deamer. 2002. Self-assembled vesicles of monocarboxylic acids and alcohols: Conditions for stability and for the encapsulation of biopolymers. BBA Biomembranes, 1559, 1-9.
Dworkin, J. P., 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.
Monnard, P.-A, C. L. Apel, A. Kanavarioti and D. W. Deamer 2002. Influence of ionic solutes on self-assembly and polymerization processes related to early forms of life: Implications for a prebiotic aqueous medium. Astrobiology 2:213-219.
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.